fix: Handle classes with multiple annotations

fixes #191

Previously the class would only be marked as injectable if the first
annotation is one of the injectable annotation. After the fix, it is
marked as injectable if any of annotaion is injectable.

The fix has been validated by 
- checking that the `FooBar` type factory is generated in the original angular.dart issue
- checking that it works by adding a `@Deprecated` annotation in the example