Simplify RubyGems publishing step in release workflow

Author: Syati

.github/workflows/release.yml

@@ -40,14 +40,8 @@ jobs:
       run: gem build structured_params.gemspec
 
     - name: Publish to RubyGems
-      run: |
-        mkdir -p $HOME/.gem
-        touch $HOME/.gem/credentials
-        chmod 0600 $HOME/.gem/credentials
-        printf -- "---\n:rubygems_api_key: ${GEM_HOST_API_KEY}\n" > $HOME/.gem/credentials
-        gem push *.gem
-      env:
-        GEM_HOST_API_KEY: ${{ secrets.RUBYGEMS_API_KEY }}
+      uses: rubygems/release-gem@v1
+      # No API key needed with trusted publishing!
 
     - name: Update CHANGELOG
       run: |