Backport "Always set source_partition_id from app" to 16.4
What does this MR do and why?
Backport of !133806 (merged) to %16.4
MR acceptance checklist
This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.
- 
This MR is backporting a bug fix, documentation update, or spec fix, previously merged in the default branch.  - 
The MR that fixed the bug on the default branch has been deployed to GitLab.com (not applicable for documentation or spec changes).  - 
This MR has a severity label assigned (if applicable).  - 
This MR has been approved by a maintainer (only one approval is required).  - 
Ensure the e2e:package-and-test-eejob has either succeeded or been approved by a Software Engineer in Test. 
Note to the merge request author and maintainer
If you have questions about the patch release process, please:
- Refer to the patch release runbook for engineers and maintainers for guidance.
 - Ask questions on the 
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Edited  by Marius Bobin