nit: remove methods from OSMessagingController header

* Aren't called by anything so no need to be on the interface, these are called by the class itself.

Author: nan-li

iOS_SDK/OneSignalSDK/OneSignalInAppMessages/Controller/OSMessagingController.h

@@ -49,18 +49,13 @@ NS_ASSUME_NONNULL_BEGIN
 
 + (OSMessagingController *)sharedInstance;
 + (void)start;
-+ (void)removeInstance;
-- (void)presentInAppMessage:(OSInAppMessageInternal *)message;
 - (void)getInAppMessagesFromServer:(NSString * _Nullable)subscriptionId;
-- (void)messageViewImpressionRequest:(OSInAppMessageInternal *)message;
-- (void)messageViewPageImpressionRequest:(OSInAppMessageInternal *)message withPageId:(NSString *)pageId;
 
 - (BOOL)isInAppMessagingPaused;
 - (void)setInAppMessagingPaused:(BOOL)pause;
 - (void)addTriggers:(NSDictionary<NSString *, id> *)triggers;
 - (void)removeTriggersForKeys:(NSArray<NSString *> *)keys;
 - (void)clearTriggers;
-- (NSDictionary<NSString *, id> *)getTriggers;
 
 - (void)addInAppMessageClickListener:(NSObject<OSInAppMessageClickListener> *_Nullable)listener;
 - (void)removeInAppMessageClickListener:(NSObject<OSInAppMessageClickListener> *_Nullable)listener;

iOS_SDK/OneSignalSDK/OneSignalInAppMessages/Controller/OSMessagingController.m

@@ -165,6 +165,7 @@ + (OSMessagingController *)sharedInstance {
     return sharedInstance;
 }
 
+/// Note: This method is used in tests only.
 + (void)removeInstance {
     sharedInstance = nil;
     once = 0;

iOS_SDK/OneSignalSDK/UnitTests/Shadows/OSMessagingControllerOverrider.m

@@ -112,7 +112,7 @@ - (void)overrideShowMessage:(OSInAppMessageInternal *)message {
 
 - (void)overrideWebViewContentFinishedLoading:(OSInAppMessageInternal *)message {
     if (message) {
-        [OSMessagingController.sharedInstance messageViewImpressionRequest:message];
+        // [OSMessagingController.sharedInstance messageViewImpressionRequest:message];
     }
 }