Complete test:foreman_ansible definition

This moves the specific override to the test defined in rake. This means
running test:foreman_ansible runs all required tests from core as well.
The only downside it that running rake test will run the particular test
twice.

.github/workflows/ruby_tests.yml

@@ -69,4 +69,3 @@ jobs:
         if: github.event_name != 'push'
         run: |
           bundle exec rake test:foreman_ansible
-          bundle exec rake test TEST="test/unit/foreman/access_permissions_test.rb"

lib/tasks/foreman_ansible_tasks.rake

@@ -7,6 +7,7 @@ namespace :test do
     test_dir = File.join(__dir__, '..', '..', 'test')
     t.libs << ['test', test_dir]
     t.pattern = "#{test_dir}/**/*_test.rb"
+    t.test_files = [Rails.root.join('test/unit/foreman/access_permissions_test.rb')]
     t.verbose = false
     t.warning = false
   end