Use GlExperimentBadge for analytics customizable dashboards

What does this MR do and why?

Removes the use of the deprecated BetaBadge, in favour of GLExperimentBadge.

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

How to set up and validate locally

Copy and apply this patch: pbpaste | git apply

diff --git a/ee/lib/gitlab/analytics/value_stream_dashboard/dashboards/value_streams_dashboard.yaml b/ee/lib/gitlab/analytics/value_stream_dashboard/dashboards/value_streams_dashboard.yaml
index 515fa3f639c0..51d70c78c06c 100644
--- a/ee/lib/gitlab/analytics/value_stream_dashboard/dashboards/value_streams_dashboard.yaml
+++ b/ee/lib/gitlab/analytics/value_stream_dashboard/dashboards/value_streams_dashboard.yaml
@@ -1,6 +1,7 @@
 ---
 title: Value Streams Dashboard
 description: Track key DevSecOps metrics throughout the development lifecycle.
+status: beta
 version: "2"
 panels:
   - visualization: dora_chart

1. Ensure you're using GitLab Ultimate
2. Navigate to the Value Streams Dashboard for any group
3. Validate that the Beta badge is rendered with a tooltip on hover

Related to #463489 (closed)