TF-1008 refactor some code

lib/features/mailbox/data/network/mailbox_api.dart

@@ -212,12 +212,7 @@ class MailboxAPI with HandleSetErrorMixin {
           notUpdatedError: response.notUpdated,
           notCreatedError: response.notCreated,
           notDestroyedHandlers: <SetMethodErrorHandler>{
-                (entry) {
+            (entry) => entry.value.type == SetError.notFound,
-              if (entry.value.type == SetError.notFound) {
-                return true;
-              }
-              return false;
-            }
           },
           unCatchErrorHandler: (setErrorEntry) {
             remainedErrors.add(setErrorEntry);

pubspec.lock

@@ -651,7 +651,7 @@ packages:
       name: glob
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.0"
+    version: "2.1.1"
   graphs:
     dependency: transitive
     description: