ci: exclude job build_debug on master

.gitlab-ci.yml

@@ -69,9 +69,9 @@ tests_debug:
   rules:
     - if: $CI_COMMIT_REF_NAME =~ /^wip*$/
       when: manual
-    - if: $CI_COMMIT_TAG
+    - if: '$CI_COMMIT_TAG || $CI_COMMIT_BRANCH == "master"'
       when: never
-    - if: '$CI_MERGE_REQUEST_ID || $CI_COMMIT_BRANCH == "master"'
+    - if: $CI_MERGE_REQUEST_ID
     - when: manual
   stage: tests
   variables: