Check EOF for all file types

[sarjona]

Currently, we are only checking EOF for PHP files (as described in MDLSITE-6397). However, as @scara raised in MDL-77396, it would be great to also add it to CiBoT for other file types (like CSS). @stronk7 mentioned (in case it helps to implement it): "We don't look for other files within moodle-cs. Surely we need to add a global whitespace checker to CiBoT (pretty much like the post-checks do, but in CiBoT, allowing zero cases).".