ci: Add gem release workflow (#27)

.github/workflows/release-gem.yml

@@ -0,0 +1,37 @@
+on:
+  push:
+    branches: main
+
+jobs:
+  code_quality:
+    uses: ./.github/workflows/main.yml
+  release-gem:
+    runs-on: ubuntu-latest
+    needs: code_quality
+    permissions:
+      contents: write
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: '0'
+          ref: ${{github.head_ref}}
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: 3.3
+      - name: Setup
+        run: |
+          git config user.email "[email protected]"
+          git config user.name "Max VelDink"
+          mkdir -p $HOME/.gem
+          touch $HOME/.gem/credentials
+          chmod 0600 $HOME/.gem/credentials
+          printf -- "---\n:rubygems_api_key: ${GEM_HOST_API_KEY}\n" > $HOME/.gem/credentials
+        env:
+          GEM_HOST_API_KEY: "${{secrets.RUBY_GEMS_PUSH_API_KEY}}"
+      - name: Install
+        run: gem install gemsmith
+      - name: Publish
+        run: gemsmith --publish