After getting more context on databricks repo in details,

Currently databricks doesn't support checkout of repo to specific commit.

databricks provides only limited functionality mentioned below

• Add a repo and connect remotely later
• Clone a repo connected to a remote repo
• Pull latest changes from the remote Git repository
• Merge branches
• Rebase a branch on another branch
• Resolve merge conflicts

more reference, https://docs.databricks.com/repos/git-operations-with-repos.html

all other git activity can be done only via the git platform

like checkout to specific version of git.