Investigate null serialization on JsonRPCPlugin's JsonSerializerOptions options

[nachmore]

More context: #1314 (comment)

[github-actions]

This issue is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 5 days.

[github-actions]

This issue is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 5 days.

[github-actions]

This issue is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 5 days.

[github-actions]

This issue is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 5 days.

[github-actions]

This issue was closed because it has been stale for 7 days with no activity. If you feel this issue still needs attention please feel free to reopen.