@Nonnull
    public static <T> T provide(@Nonnull Class<T> clazz, @Nonnull T instance) {
        return provide(clazz, instance, ServicePriority.Normal);
    }
Provides a service.

@param clazz the service class
@param instance the service instance
@param <T> the service class type
@return the same service instance
helper/src/main/java/me/lucko/helper/Services.java