Merge branch 'charlesmchen/profileSaveDeadlock' into hotfix/2.17.1

Signal/src/Profiles/OWSProfileManager.m

@@ -243,6 +243,7 @@ const NSUInteger kOWSProfileManager_MaxAvatarDiameter = 640;
         OWSAssert([userProfile isEqual:userProfileCopy]);
     }
  
+    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
         // Make sure to save on the local db connection for consistency.
         [self.dbConnection readWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
             [userProfileCopy saveWithTransaction:transaction];
@@ -280,6 +281,7 @@ const NSUInteger kOWSProfileManager_MaxAvatarDiameter = 640;
                             }];
             }
         });
+    });
 }
 
 - (void)ensureLocalProfileCached