fix:1、修复bug。2、更换sdk

Assets/MaxSdk/AppLovin/Plugins/iOS/MAUnityAdManager.m

@@ -1987,6 +1987,8 @@ static ALUnityBackgroundCallback backgroundCallback;
 
 - (NSString *)requestLatencyMillisFromRequestLatency:(NSTimeInterval)requestLatency
 {
+    if ( requestLatency == -1 ) return @"-1";
+    
     // Convert latency from seconds to milliseconds to match Android.
     long requestLatencyMillis = requestLatency * 1000;
     return @(requestLatencyMillis).stringValue;

Assets/MaxSdk/AppLovin/Plugins/iOS/MAUnityPlugin.mm

@@ -8,7 +8,7 @@
 
 #import "MAUnityAdManager.h"
 
-#define VERSION @"8.6.2"
+#define VERSION @"8.6.4"
 #define NSSTRING(_X) ( (_X != NULL) ? [NSString stringWithCString: _X encoding: NSStringEncodingConversionAllowLossy].al_stringByTrimmingWhitespace : nil)
 
 @interface NSString (ALUtils)