Builds not being triggered after migration to github app

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- [X] I have checked to see if my question is addressed in the [FAQ](https://github.com/aws-amplify/amplify-hosting/blob/master/FAQ.md).
- [X] I have [searched for duplicate or closed issues](https://github.com/aws-amplify/amplify-hosting/issues?q=is%3Aissue+).
- [X] I have read the guide for [submitting bug reports](https://github.com/aws-amplify/amplify-hosting/blob/master/CONTRIBUTING.md).
- [X] I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.

### App Id

d3o2mfqbaswdfz

### Region

us-west-2

### Amplify Hosting feature

Not applicable

### Describe the bug

New commits are not triggering builds after going through the "Migrate to our GitHub App" steps. Prior to going through those migration steps new builds would be triggered upon commit. Within Github the app appears to be configured correctly and has access to the appropriate repo etc, and I also receive a success message from within Amplify.

I do not appear to have any webhooks installed on the repo, so it seems possible that it's failing on the last step to finalize the installation, where it should delete the old webhooks and install new ones, possibly it only deleted the old and no new one was installed.

### Expected behavior

When I commit a change to the repo, builds will be automatically kicked off.

### Reproduction steps

1. Migrate to Github App
2. Commit change to repo
3. No build is kicked off

### Build Settings

_No response_

### Additional information

_No response_

Start with the reported GitHub App migration steps and inspect the repository's webhook configuration after migration. Reproduce the commit-triggered build failure for app d3o2mfqbaswdfz in us-west-2; done means a new commit automatically starts an Amplify build and the required webhook is present.

Written by the indexing model from the issue text.