- copy attributes to have different copies in different threads (#432)

Author: denischilik

mParticle-Apple-SDK/Data Model/MPIntegrationAttributes.m

@@ -29,7 +29,7 @@ - (nonnull instancetype)initWithIntegrationId:(nonnull NSNumber *)integrationId
     self = [super init];
     if (self) {
         _integrationId = integrationId;
-        _attributes = attributes;
+        _attributes = [attributes copy];
     }
 
     return self;

mParticle-Apple-SDK/mParticle.m

@@ -1273,13 +1273,15 @@ + (BOOL)registerExtension:(nonnull id<MPExtensionProtocol>)extension {
 
 #pragma mark Integration attributes
 - (nonnull MPKitExecStatus *)setIntegrationAttributes:(nonnull NSDictionary<NSString *, NSString *> *)attributes forKit:(nonnull NSNumber *)integrationId {
+    NSDictionary *attributesCopy = [attributes copy];
     __block MPKitReturnCode returnCode = MPKitReturnCodeSuccess;
 
     MPIntegrationAttributes *integrationAttributes = [[MPIntegrationAttributes alloc] initWithIntegrationId:integrationId attributes:attributes];
 
     if (integrationAttributes) {
         [executor executeOnMessage: ^{
-            [self.listenerController onAPICalled:_cmd parameter1:attributes parameter2:integrationId];
+            
+            [self.listenerController onAPICalled:_cmd parameter1:attributesCopy parameter2:integrationId];
 
             [[MParticle sharedInstance].persistenceController saveIntegrationAttributes:integrationAttributes];
         }];