Database: fix App Check token refresh (#8549)

* Database: fix App Check token refresh

* Changelog

FirebaseDatabase/CHANGELOG.md

@@ -1,3 +1,6 @@
+# v8.7.0
+- [fixed] Fixed Firebase App Check token periodic refresh. (#8544)
+
 # v8.5.0
 - [fixed] FirebaseDatabase `getData()` callbacks are now called on the main thread. (#8247)
 

FirebaseDatabase/Sources/Core/FPersistentConnection.m

@@ -1302,7 +1302,7 @@ static void reachabilityCallback(SCNetworkReachabilityRef ref,
 }
 
 - (void)sendAppCheckToken:(NSString *)token {
-    NSDictionary *requestData = @{kFWPRequestAppCheckToken : self.authToken};
+    NSDictionary *requestData = @{kFWPRequestAppCheckToken : token};
     [self sendAction:kFWPRequestActionAppCheck
                 body:requestData
            sensitive:YES