functional_tests: Only select app under test for new backup

Signed-off-by: James Valleroy <jvalleroy@mailbox.org>
2 jobs for backups-epic in 12 minutes and 9 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Test
passed #45398
run-unit-tests

00:05:11

23.38%
 
  Package
passed #45399
build-debian-package

00:06:57