[PM-34710] Add workflow to automatically label a PR by change type

[djsmith85]

🎟️ Tracking

https://bitwarden.atlassian.net/browse/PM-34710

Depends on bitwarden/gh-actions#829

📔 Objective

Adds a workflow that gets triggered when a PR is opened, synchronized or re-opened. It calls a composite action living in bitwarden/gh-actions and passes the PR number and any existing labels to it. The composite action looks for a configuration file (.github/label-pr.json) and tries to match the change type via PR title and/or changed files.

It then applies one of the labels t:* to the PR.

These change type labels are then used to create categories for the Github release notes.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 61.20%. Comparing base (dbf6308) to head (d61838d).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7850      +/-   ##
==========================================
- Coverage   65.69%   61.20%   -4.49%     
==========================================
  Files        2209     2209              
  Lines       97750    97750              
  Branches     8816     8816              
==========================================
- Hits        64216    59832    -4384     
- Misses      31316    35795    +4479     
+ Partials     2218     2123      -95     

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