Merge pull request #841 from nextcloud/feat/tool/precache_flutter

feat(tool): precache flutter if not run in CI

tool/setup.sh

@@ -7,5 +7,10 @@ for package in $(yq -r ".dev_dependencies | keys | .[]" pubspec.yaml); do
   dart pub global activate "$package" "$version"
 done
 echo "y" | fvm install
+
+if [ ! -v GITHUB_REPOSITORY ]; then
+  fvm flutter precache
+fi
+
 melos bootstrap
 fvm dart run husky install