Missing runtime dependency on lxml

On my test install, migrate fails this morning:

Apr 22 12:53:36 debusine systemd[1]: Starting debusine-server-migrate.service - Migrate Debusine Server to latest database schema...
Apr 22 12:53:38 debusine debusine-admin[45478]: Traceback (most recent call last):
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/template/backends/django.py", line 128, in get_package_libraries
Apr 22 12:53:38 debusine debusine-admin[45478]:     module = import_module(entry[1])
Apr 22 12:53:38 debusine debusine-admin[45478]:              ^^^^^^^^^^^^^^^^^^^^^^^
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3.11/importlib/__init__.py", line 126, in import_module
Apr 22 12:53:38 debusine debusine-admin[45478]:     return _bootstrap._gcd_import(name[level:], package, level)
Apr 22 12:53:38 debusine debusine-admin[45478]:            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "<frozen importlib._bootstrap>", line 1206, in _gcd_import
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "<frozen importlib._bootstrap>", line 1178, in _find_and_load
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "<frozen importlib._bootstrap>", line 1149, in _find_and_load_unlocked
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "<frozen importlib._bootstrap_external>", line 940, in exec_module
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/debusine/web/templatetags/tests/test_debusine.py", line 21, in <module>
Apr 22 12:53:38 debusine debusine-admin[45478]:     from debusine.test.django import TestCase
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/debusine/test/__init__.py", line 12, in <module>
Apr 22 12:53:38 debusine debusine-admin[45478]:     from debusine.test.base import TestCase
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/debusine/test/base.py", line 30, in <module>
Apr 22 12:53:38 debusine debusine-admin[45478]:     import lxml
Apr 22 12:53:38 debusine debusine-admin[45478]: ModuleNotFoundError: No module named 'lxml'
Apr 22 12:53:38 debusine debusine-admin[45478]: The above exception was the direct cause of the following exception:
Apr 22 12:53:38 debusine debusine-admin[45478]: Traceback (most recent call last):
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/bin/debusine-admin", line 8, in <module>
Apr 22 12:53:38 debusine debusine-admin[45478]:     sys.exit(main())
Apr 22 12:53:38 debusine debusine-admin[45478]:              ^^^^^^
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/debusine/__main__.py", line 56, in main
Apr 22 12:53:38 debusine debusine-admin[45478]:     execute_from_command_line(sys.argv)
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/core/management/__init__.py", line 442, in execute_from_command_line
Apr 22 12:53:38 debusine debusine-admin[45478]:     utility.execute()
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/core/management/__init__.py", line 436, in execute
Apr 22 12:53:38 debusine debusine-admin[45478]:     self.fetch_command(subcommand).run_from_argv(self.argv)
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/core/management/base.py", line 412, in run_from_argv
Apr 22 12:53:38 debusine debusine-admin[45478]:     self.execute(*args, **cmd_options)
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/core/management/base.py", line 458, in execute
Apr 22 12:53:38 debusine debusine-admin[45478]:     output = self.handle(*args, **options)
Apr 22 12:53:38 debusine debusine-admin[45478]:              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/core/management/base.py", line 106, in wrapper
Apr 22 12:53:38 debusine debusine-admin[45478]:     res = handle_func(*args, **kwargs)
Apr 22 12:53:38 debusine debusine-admin[45478]:           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/core/management/commands/migrate.py", line 100, in handle
Apr 22 12:53:38 debusine debusine-admin[45478]:     self.check(databases=[database])
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/core/management/base.py", line 485, in check
Apr 22 12:53:38 debusine debusine-admin[45478]:     all_issues = checks.run_checks(
Apr 22 12:53:38 debusine debusine-admin[45478]:                  ^^^^^^^^^^^^^^^^^^
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/core/checks/registry.py", line 88, in run_checks
Apr 22 12:53:38 debusine debusine-admin[45478]:     new_errors = check(app_configs=app_configs, databases=databases)
Apr 22 12:53:38 debusine debusine-admin[45478]:                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/core/checks/templates.py", line 60, in check_for_template_tags_with_the_same_name
Apr 22 12:53:38 debusine debusine-admin[45478]:     for module_name, module_path in get_template_tag_modules():
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/template/backends/django.py", line 105, in get_template_tag_modules
Apr 22 12:53:38 debusine debusine-admin[45478]:     for name in get_package_libraries(pkg):
Apr 22 12:53:38 debusine debusine-admin[45478]:   File "/usr/lib/python3/dist-packages/django/template/backends/django.py", line 130, in get_package_libraries
Apr 22 12:53:38 debusine debusine-admin[45478]:     raise InvalidTemplateLibrary(
Apr 22 12:53:38 debusine debusine-admin[45478]: django.template.library.InvalidTemplateLibrary: Invalid template library specified. ImportError raised when trying to load 'debusine.web.te>
Apr 22 12:53:38 debusine systemd[1]: debusine-server-migrate.service: Main process exited, code=exited, status=1/FAILURE

Presumably fallout from !1792 (merged)