test: use GH Actions

Author: FezVrasta

.github/workflows/tests.yml

@@ -0,0 +1,18 @@
+name: Unit Tests
+
+on: [push, pull_request]
+
+env:
+  CI: true
+
+jobs:
+  checks:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: CultureHQ/actions-yarn@master
+        with:
+          args: install
+      - uses: CultureHQ/actions-yarn@master
+        with:
+          args: test