Bug: fairly reproducible crasher in ConsentList - concurrency data access race on property storage

[bwcDvorak]

Describe the bug

Reported by partner:
`we are seeing a fairly reproducible crash issue inside XMTP framework with the ConsentList. It appears to be a concurrency data access race on the property storage, as ConsentList is declared as a class rather than a struct.

This is latest main (commit f5bdaf5); we just updated it from commit (98208aa) so I think whatever change is causing it happened between those two points.`

Expected behavior

No crash

Steps to reproduce the bug

No response