Review various CI dependencies built on (es|style)lintignore files

With MDL-71736 we are stopping to bundle both the .eslintignore and .stylelintignore files with core. Instead, they are created when needed.

This issue is about to check all the local_ci checks that may be dependent of those files existence or perform checks against those files.

Also, take a quick look to other tools (codechecker, moodlecheck, moodle-plugin-ci...) to verify that there isn't any dependency/use there.