chore: work around Node.js 22 / npm issue (#352)

Running `npm install -g npm@latest` on Node.js 22.22.2 (which bundles npm 10.9.7) fails with `MODULE_NOT_FOUND: promise-retry`. This happens because npm 11.12.0 removed `promise-retry` from its bundle (in favor of `@gar/promise-retry`). During the self-upgrade, the reify step deletes `promise-retry` from disk, and then the still-running 10.x process hits a lazy `require('promise-retry')` in `_linkBins` and blows up.

The root cause has already been fixed upstream (npm/cli#9152) and released on npm 10.9.8.

However, we can avoid the problem altogether by removing the `npm install -g@latest` step. It was initially added because it was needed for Trusted Publishing at the time, but nowadays the bundled npm is modern enough that we don’t need to force the latest version anymore.

Author: mathiasbynens

.github/workflows/publish-on-tag.yml

@@ -19,8 +19,6 @@ jobs:
         with:
           node-version-file: '.nvmrc'
           registry-url: 'https://registry.npmjs.org'
-      - name: Update npm
-        run: npm install -g npm@latest
       - name: Publish
         run: |
           npm publish --provenance --access public