Document unsupported variables for dynamic environments

Conflicts:
	doc/ci/variables/README.md

doc/ci/environments.md

@@ -247,10 +247,19 @@ declaring their names dynamically in `.gitlab-ci.yml`. Dynamic environments is
 the basis of [Review apps](review_apps/index.md).
 
 >**Note:**
-The `name` and `url` parameters can use any of the defined CI variables,
+The `name` and `url` parameters can use most of the defined CI variables,
 including predefined, secure variables and `.gitlab-ci.yml`
-[`variables`](yaml/README.md#variables).
-You however cannot use variables defined under `script` or on the Runner's side.
+[`variables`](yaml/README.md#variables). You however cannot use variables
+defined under `script` or on the Runner's side. There are other variables that
+are unsupported in environment name context:
+- `CI_JOB_ID`
+- `CI_JOB_TOKEN`
+- `CI_BUILD_ID`
+- `CI_BUILD_TOKEN`
+- `CI_REGISTRY_USER`
+- `CI_REGISTRY_PASSWORD`
+- `CI_REPOSITORY_URL`
+- `CI_ENVIRONMENT_URL`
 
 GitLab Runner exposes various [environment variables][variables] when a job runs,
 and as such, you can use them as environment names. Let's add another job in

doc/ci/variables/README.md

@@ -568,12 +568,15 @@ You can find a full list of unsupported variables below:
 - `CI_REPOSITORY_URL`
 - `CI_ENVIRONMENT_URL`
 
+These variables are also not supported in a contex of a
+[dynamic environment name][dynamic-environments].
+
 ### Secret variables with an environment scope
 
 We do support secret variables defined with an environment scope. Given that
 there is a secret variable `$STAGING_SECRET` defined in a scope of
-`review/staging/*`, following job is going to be created, based on the
-matching variable expression.
+`review/staging/*`, following job that is using dynamic environments feature,
+is going to be created, based on the matching variable expression.
 
 ```yaml
 my-job:
@@ -599,4 +602,5 @@ my-job:
 [triggers]: ../triggers/README.md#pass-job-variables-to-a-trigger
 [subgroups]: ../../user/group/subgroups/index.md
 [builds-policies]: ../yaml/README.md#only-and-except-complex
+[dynamic-environments]: ../environments.md#dynamic-environments
 [trigger-job-token]: ../triggers/README.md#ci-job-token