Dependabot rebase command reverts edits to PR title

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Package ecosystem

all

### Package manager version

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### Language version

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### Manifest location and content before the Dependabot update

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### dependabot.yml content

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### Updated dependency

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### What you expected to see, versus what you actually saw

Dependabot created a PR with a title like `chore: bump the all group across 1 directory with 4 updates`. My CI system renamed the title to prepend a ticket to the title like `TICKET-123 chore: bump the all group across 1 directory with 4 updates`. When using `@dependabot rebase` I get
```
dependabot Bot changed the title TICKET-123 chore: bump the all group with 4 updates chore: bump the all group across 1 directory with 4 updates
```

This didn't happen before, please don't revert PR title edits.

### Native package manager behavior

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### Images of the diff or a link to the PR, issue, or logs

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### Smallest manifest that reproduces the issue

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Start by tracing the @dependabot rebase command and the PR title update flow in Dependabot Core. Reproduce the issue with a CI-prefixed title, then verify that rebasing preserves the edited title instead of restoring the generated Dependabot title.

Written by the indexing model from the issue text.