[9.18] enforce system test file and name conventions with danger CI
Backport of MR !8254 (merged)
There's no need to backport commit 546212b7, because it has already been added in 3b6ca76f
Backport of MR !8254 (merged)
There's no need to backport commit 546212b7, because it has already been added in 3b6ca76f