feat: add RSpec and Rubocop workflows

.github/workflows/rspec.yml

@@ -0,0 +1,26 @@
+name: RSpec
+
+on:
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: '2.7.7'
+        bundler-cache: true
+
+    - name: Install dependencies
+      run: |
+        gem install bundler
+        bundle install --jobs 4 --retry 3
+
+    - name: Run RSpec
+      run: bundle exec rspec

.github/workflows/rubocop.yml

@@ -0,0 +1,26 @@
+name: Rubocop
+
+on:
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: '2.7.7'
+        bundler-cache: true
+
+    - name: Install dependencies
+      run: |
+        gem install bundler
+        bundle install --jobs 4 --retry 3
+
+    - name: Run RuboCop
+      run: bundle exec rubocop