[deps] BRE: Update mariadb Docker tag to v12

[renovate]

This PR contains the following updates:

Package	Update	Change
mariadb	major	10 → 12

---

Configuration

📅 Schedule: Branch creation - "every 2nd week starting on the 2 week of the year before 4am on Monday" (UTC), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, check this box

---

This PR was generated by Mend Renovate. View the repository job log.

[bitwarden-bot]

Internal tracking:

• ID: PM-32939
• Link: https://bitwarden.atlassian.net/browse/PM-32939

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 56.45%. Comparing base (d1a5c4d) to head (f21c3bb).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #7119   +/-   ##
=======================================
  Coverage   56.45%   56.45%           
=======================================
  Files        2013     2013           
  Lines       88098    88098           
  Branches     7860     7860           
=======================================
  Hits        49739    49739           
  Misses      36543    36543           
  Partials     1816     1816           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.