Automatically check that PRs to the latest branch pass all tests

.github/workflows/pr_tests_latest.yml

@@ -0,0 +1,30 @@
+# This workflow will install Exhibit and its Python dependencies and run the tests
+
+name: Testing Pull Requests
+
+on:
+  pull_request:
+    branches: [ "latest" ]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python 3.12
+      uses: actions/setup-python@v3
+      with:
+        python-version: "3.12"
+    - name: Install Exhibit and dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install -e .
+        if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+    - name: Test with unittest
+      run: |
+        python -m unittest