Do not run Generic.PHP.DisallowShortOpenTag on .yml files

I can work on a MR and add test coverage if this is an agreed way forward.

I have a project that started throw 15 phpcs errors of the exact type mentioned in the IS and also one other, all in .yml files. I can't personally see what useful feedback we would get from running a php check against .yml files.

jonathan1055 → changed the visibility of the branch 3535411-exclude-some-sniffs-on-yml-files to hidden.

Coder is being used to check some useful things in .yml files such as #2841649: Add sniff for _access: 'TRUE' in Drupal 8 routing.yml → and probably others. I think most php codesniffer rules will not trigger in .yml files, but some might, for example the one in this issue. Could you link to your pipeline job, or show the file(s) and sniff(s) that are incorrectly flagged. Then they could be excluded here too.

I have created https://github.com/pfrenssen/coder/pull/268

I can add test coverage if this is required.