fix(query): correct this scope of setters in update query

Fix #7876 re: #4185
`this` inside setters will be a Query when executing an update query.

Author: Fonger

lib/helpers/query/castUpdate.js

@@ -386,7 +386,7 @@ function castUpdateVal(schema, val, op, $conditional, context, path) {
       ++arrayDepth;
     }
 
-    let tmp = schema.applySetters(Array.isArray(val) ? val : [val]);
+    let tmp = schema.applySetters(Array.isArray(val) ? val : [val], context);
 
     for (let i = 0; i < additionalNesting; ++i) {
       tmp = tmp[0];