Move Ubuntu / lint testing to GitHub actions

Signed-off-by: Tim Smith <tsmith@chef.io>

.github/workflows/lint.yml

@@ -0,0 +1,20 @@
+---
+name: lint
+
+'on':
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  chefstyle:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: 2.5
+        bundler-cache: true
+    - uses: r7kamura/rubocop-problem-matchers-action@v1 # this shows the failures in the PR
+    - run: bundle exec cookstyle

.github/workflows/unit.yml

@@ -0,0 +1,23 @@
+---
+name: unit
+
+'on':
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby: ['2.5', '2.6', '2.7', '3.0']
+    name: Unit test on ${{ matrix.os }} with Ruby ${{ matrix.ruby }}
+    steps:
+      - uses: actions/checkout@v2
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          bundler-cache: true
+      - run: bundle exec rake spec