gitlab-ci: remove regex_check and line_limit jobs

These two are too specific for a project like this and satisfying them
is pretty much extra chore. The actual submodules and relevant cmake
logic will be removed in the future as well, possibly as part of a
migration towards meson.

.gitlab-ci.yml

@@ -39,24 +39,6 @@ cache:
   - mkdir build
   - cd build
 
-line_limit:
-  stage: analyse
-  needs: []
-  allow_failure: true
-  script:
-    - *setup_build
-    - cmake -DDOC:STRING=OFF -DLINE_LIMIT:BOOL=ON -DWERROR:BOOL=ON ..
-    - make line_limit
-
-regex_check:
-  stage: analyse
-  needs: []
-  allow_failure: true
-  script:
-    - *setup_build
-    - cmake -DDOC:STRING=OFF -DREGEX_CHECK:BOOL=ON -DWERROR:BOOL=ON ..
-    - make regex_check
-
 sphinx_html:
   stage: test
   needs: []