Add github actions for ubuntu (#467)

.github/workflows/tests.yaml

@@ -0,0 +1,22 @@
+name: Tests
+on: [push]
+jobs:
+  Ubuntu-Tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Install libpcap
+        run: sudo apt-get install -y libpcap-dev
+
+      - name: Initialize submodules
+        run: git submodule init && git submodule update
+
+      - name: Initialize build system
+        run: mkdir build && cd build && cmake ..
+
+      - name: Build tests
+        run: cmake --build build --target tests
+
+      - name: Run tests
+        run: ctest build