Mark flakey tests as blacklisted for worker mode

.buildkite/worker-blacklist

@@ -25,4 +25,10 @@ Members from the gap are included in gappy incr LL sync
 
 Leaves are present in non-gapped incremental syncs
 
-Old leaves are present in gapped incremental syncs
\ No newline at end of file
+Old leaves are present in gapped incremental syncs
+
+User sees updates to presence from other users in the incremental sync.
+
+Gapped incremental syncs include all state changes
+
+Old members are included in gappy incr LL sync if they start speaking