Update .gitlab-ci.yml - follow recommended setup procedure

.gitlab-ci.yml

@@ -9,7 +9,8 @@ build:
   # instead of calling g++ directly you can also use some build toolkit like make
   # install the necessary build tools when needed
   before_script:
-    - apt update && apt -y install meson ninja
+    - apt update && apt -y install python3 python3-pip python3-setuptools python3-wheel ninja-build
+    - pip3 install --user meson
   script:
     - meson build
   #artifacts: