chore(actions): add automated testing

.github/workflows/test.yml

@@ -0,0 +1,25 @@
+name: Tests
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Setup CMake
+        uses: jwlawson/actions-setup-cmake@v1.14
+      - name: Setup Ninja
+        uses: seanmiddleditch/gha-setup-ninja@master
+      - name: Configure and build
+        run: |
+          cmake -G Ninja -B build
+          cd build
+          ninja
+      - name: Run tests
+        run: ./build/runtests