Changing badges to use parentheses not brackets

Previously, we used brackets to denote the tier badges,
but this made Kramdown, the docs site Markdown renderer,
show many warnings when building the site. This is now
fixed by using parentheses instead of square brackets.

This was caused by [PREMIUM] looking like a link to
Kramdown, which couldn't find a URL there.

See:
- https://gitlab.com/gitlab-com/gitlab-docs/merge_requests/484
- https://gitlab.com/gitlab-org/gitlab-ce/issues/63800

2 files changed, 6 insertions, 6 deletions

diff --git a/doc/user/project/milestones/burndown_charts.md b/doc/user/project/milestones/burndown_charts.md
index 7ffeb032d7f..84e08b4eeb8 100644
--- a/doc/user/project/milestones/burndown_charts.md
+++ b/doc/user/project/milestones/burndown_charts.md
@@ -1,4 +1,4 @@
-# Burndown Charts **[STARTER]**
+# Burndown Charts **(STARTER)**
 
 > **Notes:**
 > - [Introduced](https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/1540) in [GitLab Starter](https://about.gitlab.com/pricing/) 9.1 for project milestones.
diff --git a/doc/user/project/milestones/index.md b/doc/user/project/milestones/index.md
index 6cd866b5c0d..b0745b1e2c5 100644
--- a/doc/user/project/milestones/index.md
+++ b/doc/user/project/milestones/index.md
@@ -84,9 +84,9 @@ From the project issue/merge request list pages and the group issue/merge reques
 ### Filtering in issue boards
 
 - From [project issue boards](../issue_board.md), you can filter by both group milestones and project milestones in the [search and filter bar](../../search/index.md#issue-boards).
-- From [group issue boards](../issue_board.md#group-issue-boards-premium), you can filter by only group milestones in the [search and filter bar](../../search/index.md#issue-boards). **[PREMIUM]**
-- From [project issue boards](../issue_board.md), you can filter by both group milestones and project milestones in the [issue board configuration](../issue_board.md#configurable-issue-boards-starter). **[STARTER]**
-- From [group issue boards](../issue_board.md#group-issue-boards-premium) you can filter by only group milestones in the [issue board configuration](../issue_board.md#configurable-issue-boards-starter). **[STARTER]**
+- From [group issue boards](../issue_board.md#group-issue-boards-premium), you can filter by only group milestones in the [search and filter bar](../../search/index.md#issue-boards). **(PREMIUM)**
+- From [project issue boards](../issue_board.md), you can filter by both group milestones and project milestones in the [issue board configuration](../issue_board.md#configurable-issue-boards-starter). **(STARTER)**
+- From [group issue boards](../issue_board.md#group-issue-boards-premium) you can filter by only group milestones in the [issue board configuration](../issue_board.md#configurable-issue-boards-starter). **(STARTER)**
 
 ### Special milestone filters
 
@@ -124,13 +124,13 @@ These features are only available for project milestones and not group milestone
 - Participants and labels that are used in issues and merge requests that have the milestone assigned are displayed.
 - [Burndown chart](#project-burndown-charts-starter).
 
-### Project Burndown Charts **[STARTER]**
+### Project Burndown Charts **(STARTER)**
 
 For project milestones in [GitLab Starter](https://about.gitlab.com/pricing), a [burndown chart](burndown_charts.md) is in the milestone view, showing the progress of completing a milestone.
 
 ![burndown chart](img/burndown_chart.png)
 
-### Group Burndown Charts **[PREMIUM]**
+### Group Burndown Charts **(PREMIUM)**
 
 For group milestones in [GitLab Premium](https://about.gitlab.com/pricing), a [burndown chart](burndown_charts.md) is in the milestone view, showing the progress of completing a milestone.