Update actions/upload-artifact version in CI workflow

This PR updates the version number on `actions/upload-artifact` in `.github/workflows/build-and-check.yml` in order to silence the following warning:

> The following actions use a deprecated Node.js version and will be forced to run on node20: actions/upload-artifact@v3. For more info: https://github.blog/changelog/2024-03-07-github-actions-all-actions-will-run-on-node20-instead-of-node16-by-default/

https://github.com/actions/upload-artifact says:

> actions/upload-artifact@v3 is scheduled for deprecation on November 30, 2024. [Learn more.](https://github.blog/changelog/2024-04-16-deprecation-notice-v3-of-the-artifact-actions/) Similarly, v1/v2 are scheduled for deprecation on June 30, 2024. Please update your workflow to use v4 of the artifact actions. This deprecation will not impact any existing versions of GitHub Enterprise Server being used by customers.

Author: esabol

.github/workflows/build-and-check.yml

@@ -75,7 +75,7 @@ jobs:
       uses: rlespinasse/github-slug-action@v4
 
     - name: Upload artifacts
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       if: success() || failure()
       with:
         name: ${{ env.GITHUB_REF_SLUG_URL }}-pg${{ matrix.pg_version }}-use-healpix-${{ matrix.use_healpix }}-${{ github.run_id }}