Add permissions for GitHub Actions release job

Author: jackmatt2

.github/workflows/release.yml

@@ -7,6 +7,8 @@ jobs:
   release:
     name: Release to Maven Central, Tag & Release
     runs-on: ubuntu-latest
+    permissions:
+      contents: write
     steps:
       - uses: actions/checkout@v2
       - name: Generate tag version