ci: add go mod tidy verification step to release workflow

Author: yfodil

.github/workflows/release.yml

@@ -30,6 +30,11 @@ jobs:
         with:
           go-version: 1.24.0
 
+      - name: Verify go.mod is tidy
+        run: |
+          go mod tidy
+          git diff --exit-code
+
       - name: Import GPG key
         id: import_gpg
         uses: crazy-max/ghaction-import-gpg@v6