Jenkins: Use personal credentials for project
Add the user's credentials under Global security and then allow project based Matrix Authorization Strategy per project as shown:
I found the answer in this mailing list entry:
In short: You need to
- install and activate the Authorize Projects Plugin,
- enable "run as specific user" strategy in global security settings,
- enable this for the project in question.
This allows you to use the credentials for this specific user.
Enabling ssh-agent is the final step to make this work conveniently.