Install ccache before run on macOS

.gitlab-ci.yml

@@ -130,11 +130,11 @@ Debian_Clang_tests:
     - ccache/
   script:
     - rm -fr build  # remove the build directory
+    - CI/before_install.osx.sh
     - export CCACHE_BASEDIR="$(pwd)"
     - export CCACHE_DIR="$(pwd)/ccache"
     - mkdir -pv "${CCACHE_DIR}"
     - ccache -z -M "${CCACHE_SIZE}"
-    - CI/before_install.osx.sh
     - CI/before_script.osx.sh
     - cd build; make -j $(sysctl -n hw.logicalcpu) package
     - for dmg in *.dmg; do mv "$dmg" "${dmg%.dmg}_${CI_COMMIT_REF_NAME}_${CI_JOB_ID}.dmg"; done