Auto merge pull requests when all checks succeeded via WebUI

[6543]

to work use #19648 or rewrite ...

[wxiaoguang]

Copy the comments here (some thoughts about how to refactor this UI):

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Either rewrite the merge form with Vue.

Or, just add an checkbox Auto merge when succeed to merge UI, then these code do not need to be copied twice.

• When the PR is merge-able, hide the chekcbox, show merge buttons.
• When the PR is not merge-able, show the checkbox and hide merge buttons. Only when the checkbox is checked, then show the merge buttons.

(ps: the checkbox could be some other component, maybe switch between AutoMerge and ManualMerge)

[viceice]

Any idea why the automerge feature isn't visuble to me?

I thought for admins both options shoulod be available 🤔

[6543]

please open a new issue or chat via matrix/discord first ...

if you open a issue, of course link to this issue :)

my guess: you did not protect the target branch