CI: use pip packages instead of apt

.gitlab-ci.yml

@@ -57,17 +57,17 @@ Build the docker image:
 flake8:
   extends: .static_analysis_base
   script:
-   - sudo apt update && sudo apt install -y flake8 && python -m flake8 --ignore=E402 --max-line-length=120 $PWD/decloud
+   - pip install flake8 && flake8 --ignore=E402 --max-line-length=120 $PWD/decloud
 
 pylint:
   extends: .static_analysis_base
   script:
-  - sudo apt update && sudo apt install -y pylint && pylint --disable=too-many-nested-blocks,too-many-locals,too-many-statements,too-few-public-methods,too-many-instance-attributes,too-many-arguments,invalid-name,cell-var-from-loop,too-many-branches,too-many-ancestors --ignored-modules=tensorflow,git,rtree,scipy,tensorboard,libamalthee,pandas --max-line-length=120 $PWD/decloud
+   - pip install pylint && pylint --disable=too-many-nested-blocks,too-many-locals,too-many-statements,too-few-public-methods,too-many-instance-attributes,too-many-arguments,invalid-name,cell-var-from-loop,too-many-branches,too-many-ancestors --ignored-modules=tensorflow,git,rtree,scipy,tensorboard,libamalthee,pandas --max-line-length=120 $PWD/decloud
 
 codespell:
   extends: .static_analysis_base
   script:
-    - sudo pip install codespell && codespell --skip="*.png,*.template,*.pbs,*.jpg,*git/lfs*"
+   - pip install codespell && codespell --skip="*.png,*.template,*.pbs,*.jpg,*git/lfs*"
 
 .applications_test_base:
   image: $TEST_IMAGE_NAME