Feature: A flag to clean up old/broken Git commits and PR links.

[jemyto]

Work Item external links get broken if repositories are deleted and imported again.

My scenario is the following:

1. I've imported repositories to the target project I want to migrate to.
2. Run the tool to migrated all work items.
3. Deleted and re-imported repositories to the target project in order to take all the latest changes.
4. Now all work item commit/PR links are broken because the IDs are different.
   
5. Triggered a new run with only LinkMigration flag to update links.
6. New links were added but the broken links still stay!

My solution to clean up broken links was to implement a new flag in the WorkItemMigrationConfig in order to delete previous Git links.

[MrHinsh]

Deleting the repos and reimporting them is a very time-consuming solution to the problem. Using multiple Remotes would be much quicker.

You can add multiple remotes to a git repo to achieve this. For example, if your original repo is at https://mylocalTFS/collectionA/ProjectA/_git/ProjectA and you want to move it to https://dev.azure.com/OrgA/ProjectA/_git/ProjectA

1. git clone https://mylocalTFS/collectionA/ProjectA/_git/ProjectA
2. git remote add AzureDevOps https://dev.azure.com/OrgA/ProjectA/_git/ProjectA

Now that you have 2 remotes you can use git pull origin to pull from https://mylocalTFS/collectionA/ProjectA/_git/ProjectA and then git push AzureDevOps to push any changes to https://dev.azure.com/OrgA/ProjectA/_git/ProjectA.