Fix pipeline breaking due to libGL not being found

Fix pipeline breaking from libGL not being found by installing required dependencies. Closes #31 (closed).

.gitlab-ci.yml

@@ -20,6 +20,7 @@ stages:
   - Build Env and Test
 before_script:
   - pip install -e .[dev]
+  - apt-get update && apt install -y libgl1-mesa-glx
 
 flake8:
   image: python:3.8