After restore cache, show count of how many URLs in it

[fulldecent]

Cache is hard to set up and sometimes it breaks for weird reasons.

After the restore cache action, let's add a line to print out how many URLs are in that cache.

[fulldecent]

Error: that messed up the required key property of the prior line

Evidence: manual inspection of the YAML.

Also. If you will make further changes, please make a PR instead of an issue.

[fulldecent]

Failed, undo!

[fulldecent]

      - name: Count URLs in cache
        run: |
          URL_COUNT=$(sqlite3 cache/external-links.db "SELECT COUNT(*) FROM urls;")
          echo "Number of URLs in cache: $URL_COUNT"

This fails if the database does not exist.

Need to have an if statement there.