ci: Get rid of paths-ignore to ensure all PRs can be merged

We require jobs to succeed before a PR can be merged. If a PR only
touches files which match `paths-ignore`, the jobs won't run and the PR
can't be merged.

The number of PRs which only touch those files is small, and the extra
CI runs resulting from that can be ignored.

.github/workflows/check.yml

@@ -6,14 +6,6 @@ on:
     - main
     - 'flatpak-1.[0-9]+.x'
   pull_request:
-    paths-ignore:
-    - README.md
-    - CONTRIBUTING.md
-    - NEWS
-    - COPYING
-    - CODE_OF_CONDUCT.md
-    - uncrustify.cfg
-    - uncrustify.sh
     branches:
     - main
     - 'flatpak-1.[0-9]+.x'