I have a git repo which has branches like branch-a, branch-b, branch-c. Now, in branch-b I have mistakenly uploaded a big file (200mb). Now the overall repo has exceeded to 230mb. Whenever I do git clone, I am downloading 230mb when I only require 30mb of data. I also deleted this branch both locally and in remote. This branch has not merged with master, and its commits are of no use.
How can I reduce my repo size as if this branch had never existed? I do not want the commits to be rewritten. To delete the branch I have followed:
git checkout master
git branch -D branch-b
git push origin --delete branch-b
I am new to git so, if I could get exact steps to do this would be very helpful, I am scared of messing up the remote.