Changing the destination branch of a pull request after deletion

[tulzke]

Feature Description

branch3 -> branch2 -> branch1 -> master
Now, if we have a chain of pull requests, we cannot merge branch1 first, because all other requests to branch1 will be closed without the possibility of reopening.

In bitbucket, this was solved by the fact that when deleting a branch1, all open pull requests change the target to the branch into which branch1 was merged, in our case, this is the master.

Screenshots

Here is an example in the form of a mind map.
Schema before merge branch1:

After merge and deleting branch1:

[lunny]

Retargeting all pull requests targeted branch1 to master sounds reasonable. Or we can have a prompt dialog to let users choose when deleting?

[tulzke]

Retargeting all pull requests targeted branch1 to master sounds reasonable. Or we can have a prompt dialog to let users choose when deleting?

Only before we merge branch1. It's easy to forget to do that. Why not do it automatically, as it is implemented in Bitbucket

[github-actions]

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