ci: Add GitHub workflow for automated testing

.github/workflows/test.yml

@@ -0,0 +1,44 @@
+# This workflow will install Python dependencies and perform testing
+
+name: Test Printrun
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11", "3.12"]
+        include:
+          # Currently, unit testing requires Python 3.11+
+          - unit-test: false
+          - python-version: "3.11"
+            unit-test: true
+          - python-version: "3.12"
+            unit-test: true
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v4
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install -r requirements.txt
+
+      - name: Perform functional tests
+        run: |
+          ./pronterface.py -h
+
+      - name: Perform unit tests
+        if: ${{ matrix.unit-test }}
+        run: |
+          python -m unittest discover tests