Fix FIAM pod lib lint issue (#3102)

Author: paulb777

Firebase/InAppMessaging/Flows/FIRIAMDisplayExecutor.m

@@ -56,7 +56,10 @@ - (void)messageClicked:(FIRInAppMessagingDisplayMessage *)inAppMessage
     [appSideDelegate messageClicked:inAppMessage withAction:action];
   } else if ([appSideDelegate respondsToSelector:@selector(messageClicked:)]) {
     // Deprecated method is called only as a fall-back.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
     [appSideDelegate messageClicked:inAppMessage];
+#pragma clang diagnostic pop
   }
 
   self.isMsgBeingDisplayed = NO;