WIP Fix flaky tests

[Bushstar]

Summary

• Several CI tests have become unstable, this PR should stabilise them.

Implications

• Storage

  • [ ] Database reindex required
  • [ ] Database reindex optional
  • [ ] Database reindex not required
  • [x] None

• Consensus

  • [ ] Network upgrade required
  • [ ] Includes backward compatible changes
  • [ ] Includes consensus workarounds
  • [ ] Includes consensus refactors
  • [x] None