[expo-notifications] Smaller fixes (#6790)

# Why, How

Whilst preparing #6773 I noticed two commits that don't belong to that PR. So I created a separate one to make the other one simpler to review.

# Test Plan

Code compiles.

packages/expo-notifications/android/src/main/java/expo/modules/notifications/tokens/PushTokenModule.java

@@ -41,12 +41,12 @@ public String getName() {
 
   @Override
   public void onCreate(ModuleRegistry moduleRegistry) {
+    mEventEmitter = moduleRegistry.getModule(EventEmitter.class);
+
     // Register the module as a listener in PushTokenManager singleton module.
     // Deregistration happens in onDestroy callback.
     mPushTokenManager = moduleRegistry.getSingletonModule("PushTokenManager", PushTokenManager.class);
     mPushTokenManager.addListener(this);
-
-    mEventEmitter = moduleRegistry.getModule(EventEmitter.class);
   }
 
   @Override

packages/expo-notifications/ios/EXNotifications/EXPushTokenModule.m

@@ -5,7 +5,7 @@
 
 #import <UMCore/UMEventEmitterService.h>
 
-static const NSString *onDevicePushTokenEventName = @"onDevicePushToken";
+static NSString * const onDevicePushTokenEventName = @"onDevicePushToken";
 
 @interface EXPushTokenModule ()
 
@@ -57,7 +57,7 @@ - (void)setModuleRegistry:(UMModuleRegistry *)moduleRegistry
 
 - (NSArray<NSString *> *)supportedEvents
 {
-  return @[(NSString *)onDevicePushTokenEventName];
+  return @[onDevicePushTokenEventName];
 }
 
 - (void)startObserving
@@ -102,7 +102,7 @@ - (void)onDidRegisterWithDeviceToken:(NSData *)devicePushToken
   }
 
   if (_isBeingObserved) {
-    [_eventEmitter sendEventWithName:(NSString *)onDevicePushTokenEventName
+    [_eventEmitter sendEventWithName:onDevicePushTokenEventName
                                 body:@{ @"devicePushToken": stringToken }];
   }
 }