Add workflows

.github/workflows/rspec.yaml

@@ -0,0 +1,25 @@
+name: RSpec
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  rspec:
+    name: RSpec
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby_version:
+          - 2.6
+          - 2.7
+          - 3.0
+    steps:
+    - uses: actions/checkout@v2
+    - uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.ruby_version }}
+        bundler-cache: true
+
+    - run: bundle exec rake

.github/workflows/rubocop.yaml

@@ -0,0 +1,18 @@
+name: RuboCop
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  rubocop:
+    name: RuboCop
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: 3.0
+        bundler-cache: true
+
+    - run: bundle exec rubocop