Automate testing and code ownership

Use GitHub Actions to automate testing and static code analysis. In
addition repository contributors are specified as codeowners so that
proposed changes are seen quicker.

.github/CODEOWNERS

@@ -0,0 +1,9 @@
+# These owners will be the default owners for everything in the repo. Unless a
+# later match takes precedence, these owner(s) will be requested for review
+# when someone opens a pull request.
+* @StatusCakeDev/developers
+
+# Order is important; the last matching pattern takes the most precedence. When
+# someone opens a pull request that only modifies Ruby files, only these
+# owner(s) and not the global owner(s) will be requested for a review.
+*.rb @StatusCakeDev/developers

.github/workflows/publish.yaml

@@ -0,0 +1,24 @@
+name: publish
+on:
+  release:
+    types:
+    - published
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: "3.1"
+        bundler-cache: true
+    - name: Publish to RubyGems
+      run: |
+        mkdir -p $HOME/.gem
+        touch $HOME/.gem/credentials
+        chmod 0600 $HOME/.gem/credentials
+        printf -- "---\n:rubygems_api_key: ${RUBYGEMS_API_KEY}\n" > $HOME/.gem/credentials
+        bundle exec gem build statuscake.gemspec
+        bundle exec gem push *.gem
+      env:
+        RUBYGEMS_API_KEY: ${{ secrets.RUBYGEMS_API_KEY }}

.github/workflows/test.yaml

@@ -0,0 +1,23 @@
+name: test
+on:
+  pull_request:
+  push:
+    branches:
+    - master
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby:
+        - "3.1"
+        - "3.0"
+        - "2.7"
+    steps:
+    - uses: actions/checkout@v2
+    - uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.ruby }}
+        bundler-cache: true
+    - run: bundle exec rubocop
+    - run: bundle exec rake spec

README.md

@@ -1,4 +1,4 @@
-# statuscake-rb
+# statuscake-rb ![test](https://github.com/StatusCakeDev/statuscake-rb/workflows/test/badge.svg)
 
 **NOTE**: This library is in alpha and not production ready. Whilst it can be
 used we will not offer support until it is generally available.