chore: enhance GoReleaser and GitHub Actions workflows for GPG signing

- Added GPG signing configuration in .goreleaser.yml to support artifact signing for all artifacts.
- Updated release.yml to enforce GPG signing by setting global Git configuration options for signing commits and tags.
- Improved the signing process by utilizing the GPG fingerprint from environment variables, enhancing security and flexibility.

.github/workflows/release.yml

@@ -43,6 +43,10 @@ jobs:
         with:
           gpg_private_key: ${{ secrets.GPG_PRIVATE_KEY }}
           passphrase: ${{ secrets.PASSPHRASE }}
+          git_config_global: true
+          git_user_signingkey: true
+          git_commit_gpgsign: true
+          git_tag_gpgsign: true
 
       - name: Run GoReleaser
         uses: goreleaser/goreleaser-action@v4