[ci] avoid running pre-commit a nth+1 time

.gitlab-ci.yml

@@ -37,8 +37,6 @@ build_linux:
     - python3 ./bob/devtools/bootstrap.py -vv build
     - source ${CONDA_ROOT}/etc/profile.d/conda.sh
     - conda activate base
-    - pip install pre-commit
-    - pre-commit run --all-files
     - python3 ./bob/devtools/build.py -vv --twine-check
   artifacts:
     paths:
@@ -61,8 +59,6 @@ build_macos_intel:
     - python3 ./bob/devtools/bootstrap.py -vv build
     - source ${CONDA_ROOT}/etc/profile.d/conda.sh
     - conda activate base
-    - pip install pre-commit
-    - pre-commit run --all-files
     - python3 ./bob/devtools/build.py -vv
   artifacts:
     paths: