fix type on double quote

android/src/main/java/com/joshblour/reactnativepermissions/ReactNativePermissionsModule.java

@@ -56,7 +56,7 @@ public class ReactNativePermissionsModule extends ReactContextBaseJavaModule {
       return;
     }
 
-    if(permission.equals('notification')) {
+    if(permission.equals("notification")) {
       if (mNotificationManagerCompat.areNotificationsEnabled()) {
         promise.resolve("authorized");
       } else {
@@ -138,4 +138,4 @@ public class ReactNativePermissionsModule extends ReactContextBaseJavaModule {
     }
   }
 
-}
+}