chore: add test workflow

Author: josteph

.github/workflows/test.yml

@@ -0,0 +1,30 @@
+name: Test
+"on":
+  push:
+    branches:
+      - main
+      - dependabot/**
+  pull_request:
+    types:
+      - opened
+      - synchronize
+
+jobs:
+  test_matrix:
+    strategy:
+      matrix:
+        node-version:
+          - 14.17
+          - 16
+        os:
+          - ubuntu-latest
+    runs-on: "${{ matrix.os }}"
+    steps:
+      - uses: actions/checkout@v2
+      - name: "Use Node.js ${{ matrix.node-version }}"
+        uses: actions/setup-node@v2
+        with:
+          node-version: "${{ matrix.node-version }}"
+          cache: npm
+      - run: npm ci
+      - run: "npm run test --ci"