debian/rules: be more verbose when running the tests, in particular, show why...

debian/rules: be more verbose when running the tests, in particular, show why tests are being skipped

debian/rules

@@ -7,6 +7,8 @@ ifneq ($(VERSION_dch),$(VERSION_py))
  $(error "Version in debian/changelog doesn't match diffoscope version")
 endif
 
+export PYBUILD_TEST_ARGS = -v -r sxX
+
 %:
 	dh $@ --with python3 --with bash-completion --buildsystem=pybuild