Tests occasionally timeout on macOS 26

[cclauss]

Should we increase the timeout value or do something different?

291 passing (3s)
6 pending
1 failing

1. Canvas
   Canvas#getContext("2d"):
   Error: Timeout of 2000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves. (/Users/runner/work/node-canvas/node-canvas/test/canvas.test.js)
   at process.processImmediate (node:internal/timers:491:21)

Also, add Node.js 25.2.0 and DRY the CI strategy so it can be configured once and reused.

• https://github.blog/changelog/2025-09-18-actions-yaml-anchors-and-non-public-workflow-templates

Thanks for contributing!

• Have you updated CHANGELOG.md?