BCMA to support incremental migration (update existing repos)

Problem Definition

Currently, BCMA does not support the migration of repositories that are already present in Bitbucket Cloud. To remigrate a repository, it is necessary to first delete the repository/repositories and then re-migrate the repository/repositories.

Suggested Solution

It would be helpful if it was possible to migrate only new changes/deltas in BCMA.

From BCMA, it should be possible to remigrate and have only the newest branches, commits, and pull requests synchronised across.