ci: add build and publish steps (#40)

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

.github/workflows/rubygems.yml

@@ -16,7 +16,8 @@ jobs:
         ruby-version: ['2.7', '3.0', '3.1', '3.2', '3.3']
 
     steps:
-      - uses: actions/checkout@v4
+      - name: Checkout repository
+        uses: actions/checkout@v4
 
       - name: Set up Ruby ${{ matrix.ruby-version }}
         uses: ruby/setup-ruby@v1
@@ -58,3 +59,48 @@ jobs:
         if: matrix.ruby-version == '3.1'
         env:
           CC_TEST_REPORTER_ID: "${{ secrets.CC_TEST_REPORTER_ID }}"
+
+  build_and_publish:
+    name: Build and Publish
+    runs-on: ubuntu-latest
+
+    needs: test
+    if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+
+    permissions:
+      contents: read
+      packages: write
+
+    env:
+      RUBY_VERSION: 2.7
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+
+    - name: Set up Ruby ${{ env.RUBY_VERSION }}
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ env.RUBY_VERSION }}
+        bundler-cache: true
+
+    - name: Publish to GPR
+      run: |
+        mkdir -p "$HOME/.gem"
+        touch "$HOME/.gem/credentials"
+        chmod 0600 "$HOME/.gem/credentials"
+        printf -- "---\n:github: %s\n" "${GEM_HOST_API_KEY}" > "$HOME/.gem/credentials"
+        gem build -- *.gemspec
+        gem push --KEY github --host "https://rubygems.pkg.github.com/${OWNER}" -- *.gem
+        mkdir -p $HOME/.gem
+        touch $HOME/.gem/credentials
+        chmod 0600 $HOME/.gem/credentials
+        printf -- "---\n:github: ${GEM_HOST_API_KEY}\n" > $HOME/.gem/credentials
+        gem build *.gemspec
+        gem push --KEY github --host https://rubygems.pkg.github.com/${OWNER} *.gem
+      env:
+        GEM_HOST_API_KEY: "Bearer ${{secrets.GITHUB_TOKEN}}"
+        OWNER: ${{ github.repository_owner }}
+
+    - name: Publish to RubyGems
+      uses: rubygems/release-gem@v1