Merge branch 'document-ci-registry-in-predefined-variables' into 'master'

Document port value for CI_REGISTRY

Closes #36359

See merge request gitlab-org/gitlab!20149

doc/ci/variables/predefined_variables.md

@@ -97,7 +97,7 @@ future GitLab releases.**
 | `CI_PROJECT_TITLE`                      | 12.4   | all    | The human-readable project name as displayed in the GitLab web interface. |
 | `CI_PROJECT_URL`                        | 8.10   | 0.5    | The HTTP(S) address to access project |
 | `CI_PROJECT_VISIBILITY`                 | 10.3   | all    | The project visibility (internal, private, public) |
-| `CI_REGISTRY`                           | 8.10   | 0.5    | If the Container Registry is enabled it returns the address of GitLab's Container Registry |
+| `CI_REGISTRY`                           | 8.10   | 0.5    | If the Container Registry is enabled it returns the address of GitLab's Container Registry.  This variable will include a `:port` value if one has been specified in the registry configuration. |
 | `CI_REGISTRY_IMAGE`                     | 8.10   | 0.5    | If the Container Registry is enabled for the project it returns the address of the registry tied to the specific project |
 | `CI_REGISTRY_PASSWORD`                  | 9.0    | all    | The password to use to push containers to the GitLab Container Registry |
 | `CI_REGISTRY_USER`                      | 9.0    | all    | The username to use to push containers to the GitLab Container Registry |