Support multiple create-pull-request and push-to-pull-request-branch #17283
Description
In this run, the Repo Maintainer agentic workflow tried to create multiple pull requests in one run.
The safe output MCP collector was called multipe times and didn't fail this, and I think the aw.patch witll just get overridden and things will get all messed up.
We should support creating multiple pull requests in each run, labelling them aw-{branch-name-1}.patch, aw-{branch-name-2}.patch and so on. Change the name of aw.patch to aw-{branch-name-1}.patch even if there is only one of them.
THe code that consumes and applies pull requests will of course need updating - any other code mentioning aw.patch should get updated too .
Multiple mixes of create-pull-request and push-to-pull-request-branch should also be supported