Clean up git large files in both local & remote repositories

do this at remote server repo:

git reflog expire --expire=now --all
git gc --prune=now

do this at local server repo:

git reflog expire --expire=now --all
git gc --prune=now
git push --all --force
git push --tags --force

src: https://confluence.atlassian.com/bitbucket/reduce-repository-size-321848262.html