We are migrating a repository from Git enterprise to GitHub. But this is not happening since the repository is around 4GB in size. On analysing found out that the .pack file is huge and is around 4GB. on further drill down, we found out that there are some huge files, which are no more part of the repository was checked in at one point.
Can we effectively remove these files from the history to make the .pack file lighter? What are the steps to be followed for the same? Please help.