TUN-9800: Migrate cloudflared-ci pipelines to Gitlab CI

## Summary

This commit migrates the cloduflared ci pipelines, that built, tested and component tested the linux binaries to gitlab ci.

The only thing that is remaining to move from teamcity to gitlab are now the release pipelines that run on master.

Relates to TUN-9800

.ci/commons.gitlab-ci.yml

@@ -5,13 +5,19 @@
     - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
       when: always
     - when: never
-  # Rules to run the job only on branches that are not master. This is needed because for now
-  # we need to keep a similar behavior due to the integration with teamcity, which requires us
-  # to not trigger pipelines on tags and/or merge requests.
-  run-on-branch:
+  # Rules to run the job only on merge requests
+  run-on-mr:
     - if: $CI_COMMIT_TAG
       when: never
-    - if: $CI_PIPELINE_SOURCE != "merge_request_event" && $CI_COMMIT_BRANCH != $CI_DEFAULT_BRANCH
+    - if: $CI_PIPELINE_SOURCE == "merge_request_event"
+      when: always
+    - when: never
+  # Rules to run the job on merge_requests and master branch
+  run-always:
+    - if: $CI_COMMIT_TAG
+      when: never
+    - if: $CI_PIPELINE_SOURCE == "merge_request_event"
+    - if: $CI_COMMIT_BRANCH != null && $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
       when: always
     - when: never
 
@@ -28,4 +34,20 @@
       else
         echo "No tag present — skipping."
         exit 0
-      fi
+      fi
+
+.component-tests:
+  image: $BUILD_IMAGE
+  rules:
+    - !reference [.default-rules, run-always]
+  variables:
+    COMPONENT_TESTS_CONFIG: component-test-config.yaml
+    COMPONENT_TESTS_CONFIG_CONTENT: Y2xvdWRmbGFyZWRfYmluYXJ5OiBjbG91ZGZsYXJlZC5leGUKY3JlZGVudGlhbHNfZmlsZTogY3JlZC5qc29uCm9yaWdpbmNlcnQ6IGNlcnQucGVtCnpvbmVfZG9tYWluOiBhcmdvdHVubmVsdGVzdC5jb20Kem9uZV90YWc6IDQ4Nzk2ZjFlNzBiYjc2NjljMjliYjUxYmEyODJiZjY1
+  secrets:
+    DNS_API_TOKEN:
+      vault: gitlab/cloudflare/tun/cloudflared/_dev/_terraform_atlantis/component_tests_token/data@kv
+      file: false
+    COMPONENT_TESTS_ORIGINCERT:
+      vault: gitlab/cloudflare/tun/cloudflared/_dev/component_tests_cert_pem/data@kv
+      file: false
+  cache: {}