Add automated testing via GitHub Actions

.github/workflows/test.yml

@@ -0,0 +1,38 @@
+name: 'test'
+
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+
+jobs:
+  test:
+    name: test
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: [3.9]
+    steps:
+      - name: Checkout the repository
+        uses: actions/checkout@v2
+
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v2
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install dependencies
+        run: |
+          if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+          if [ -f requirements-test.txt ]; then pip install -r requirements-test.txt; fi
+
+      - name: Run pytest
+        run: |
+          python -m pytest --cov=simple_kp --cov-report=xml tests/
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v1
+        with:
+          file: ./coverage.xml
+          env_vars: OS,PYTHON