## Problem description
During tests we found concurrency issues in the relational table
projections. Tests got flaky if a table (e.g. organization domains) had
too many foreign keys to tables which were projected by another handler.
## Resolution
The projections of the relational tables got merged into one handler to
enforce sequential reduction of events.
## Additional info
- closes https://github.com/zitadel/zitadel/issues/11703
- closes https://github.com/zitadel/zitadel/issues/10810
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Co-authored-by: Marco Ardizzone <[email protected]>
