add --no-cache-dir to gitlab yml

.gitlab-ci.yml

@@ -3,7 +3,7 @@ build-job:
   script:
     - python3 -m venv venv
     - . venv/bin/activate
-    - pip3 install -r requirements.txt
+    - pip3 install -r requirements.txt --no-cache-dir
 
 test-job:
   stage: test