VCS: Handling of multiple open PRs

### Describe the problem

Currently, our workflow with translation management centres around PRs. Whenever a change is made to one or multiple texts, a PR is created as a mean to approve changes made in our language management tool.
This leads to rather small PRs, of which multiple can be open at the same time. The current PR-logic of Weblate can apparently not handle this.
We would prefer to keep our current process, and are therefore interested in finding a solution in the way Weblate handles PRs. We would need to find a solution for these scenarios:
- A PR is created while one or multiple PRs on the same branch are still open
- A PR is rejected in Bitbucket the changes need to be reverted in Weblate

Our VCR is Bitbucket Cloud, which does not support multiple open PRs from the same branch. This feature request is building upon https://github.com/WeblateOrg/weblate/issues/2344

### Describe the solution you would like

My understanding is that we will need to create individual branches for each PR (open to find different solutions). I see 2 options to handle these branches:
1. Creation of individual branches for every PR. All PRs point toward the push repository.
2. Checking if there is an open PR on the current branch (no. 1) and creating a new branch (no. 2) from the Tip of no. 1 if necessary. The PR of no. 2 would target no. 1. If no. 1 is merged in the meantime, no. 2 would automatically target the push branch (as described [here](https://community.atlassian.com/t5/Bitbucket-questions/If-a-pull-request-is-not-yet-closed-can-I-create-one-more-pull/qaq-p/1345302))

I see no solution to handle rejected PRs. How is this currently handled?

### Describe alternatives you have considered

_No response_

### Screenshots

_No response_

### Additional context

_No response_