ci: install osmesa

Author: jourdain

.github/workflows/test_and_release.yml

@@ -62,9 +62,13 @@ jobs:
 
     - name: Install dependencies
       run: |
-        pip install .
+        pip install .[dev]
         pip install -r tests/requirements.txt
 
+    - name: Install OSMesa for Linux
+      if: matrix.config.os == 'ubuntu-latest'
+      run: sudo apt-get install -y libosmesa6-dev
+
     - name: Run Tests
       run: |
         # Run the tests with coverage so we get a coverage report too