Added tier badges to ci/runners

doc/ci/runners/configure_runners.md

@@ -5,7 +5,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 type: reference
 ---
 
-# Configuring runners
+# Configuring runners **(FREE)**
 
 If you have installed your own runners, you can configure and secure them in GitLab.
 
@@ -556,7 +556,7 @@ the following stages:
 | Variable                        | Description                                            |
 |---------------------------------|--------------------------------------------------------|
 | `ARTIFACT_DOWNLOAD_ATTEMPTS`    | Number of attempts to download artifacts running a job |
-| `EXECUTOR_JOB_SECTION_ATTEMPTS` | [In GitLab 12.10](https://gitlab.com/gitlab-org/gitlab-runner/-/issues/4450) and later, the number of attempts to run a section in a job after a [`No Such Container`](https://gitlab.com/gitlab-org/gitlab-runner/-/issues/4450) error ([Docker executor](https://docs.gitlab.com/runner/executors/docker.html) only). |
+| `EXECUTOR_JOB_SECTION_ATTEMPTS` | In [GitLab 12.10 and later](https://gitlab.com/gitlab-org/gitlab-runner/-/issues/4450), the number of attempts to run a section in a job after a [`No Such Container`](https://gitlab.com/gitlab-org/gitlab-runner/-/issues/4450) error ([Docker executor](https://docs.gitlab.com/runner/executors/docker.html) only). |
 | `GET_SOURCES_ATTEMPTS`          | Number of attempts to fetch sources running a job      |
 | `RESTORE_CACHE_ATTEMPTS`        | Number of attempts to restore the cache running a job  |
 

doc/ci/runners/index.md

@@ -5,7 +5,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 type: reference
 ---
 
-# GitLab Build Cloud runners
+# GitLab Build Cloud runners **(FREE)**
 
 If you are using self-managed GitLab or you want to use your own runners on GitLab.com, you can
 [install and configure your own runners](https://docs.gitlab.com/runner/install/).

doc/ci/runners/runners_scope.md

@@ -5,7 +5,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 type: reference
 ---
 
-# The scope of runners
+# The scope of runners **(FREE)**
 
 Runners are available based on who you want to have access: