[deps] BRE: Update mariadb Docker tag to v12

[renovate]

This PR contains the following updates:

Package	Update	Change
mariadb	major	10 → 12

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[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).
⚠️ Report is 201 commits behind head on main.

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           

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[brandonbiete]

I think this is fine due to MariaDB backwards compatibility and it being a dev environment.