Add AuthActivityTest - #48

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4, actions/setup-java@v4, gradle/actions/setup-gradle@v3. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

Failed to restore gradle-home-v1|Linux|instrumented-tests[8ec987573c60638b285f64ab2e3834fe]-1a10a830cf0e10d26b552f1d64a6b99126619719: Error: Cache service responded with 400