fix: Avoid premature garbage collection of Client tasks

[Haptein]

Summary

Addresses #2179: Avoids client tasks being garbage collected prematurely, particularly on long-running tasks.

Information

• [ x] This PR fixes an issue.

Checklist

• [x] I have searched the open pull requests for duplicates.
• [x] If code changes were made then they have been tested.
  • [ ] I have updated the documentation to reflect the changes.
• [ ] If type: ignore comments were used, a comment is also left explaining why.
• [ ] I have updated the changelog to include these changes.