Add basic GitHub Actions setup (#41)

Author: Robert Jackson

.github/workflows/ci.yml

@@ -0,0 +1,25 @@
+name: CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: [10.x, 12.x, 14.x]
+
+    steps:
+    - uses: actions/checkout@v2
+    - uses: volta-cli/action@v1
+      with:
+        node-version: ${{ matrix.node-version }}
+    - run: yarn install --frozen-lockfile
+    - run: yarn lint:js
+    - run: yarn test

package.json

@@ -55,5 +55,9 @@
       "release": true,
       "tokenRef": "GITHUB_AUTH"
     }
+  },
+  "volta": {
+    "node": "12.21.0",
+    "yarn": "1.22.10"
   }
 }