Add CI to test on push

.github/workflows/tests.yml

@@ -0,0 +1,22 @@
+name: tests
+run-name: ${{ github.sha }} test job
+on: [push]
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout sources
+        uses: actions/checkout@v2
+
+      - name: Install stable toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          override: true
+
+      - name: Run cargo test
+        uses: actions-rs/cargo@v1
+        continue-on-error: true
+        with:
+          command: test