resourceloader: Deprecate ResourceLoaderContext::getConfig and ::getLogger

resourceloader: Deprecate ResourceLoaderContext::getConfig and ::getLogger

The methods existed for two use cases.

1. Inside ResourceLoaderContext, usage was removed with I4e4ee758cd22.
2. In Module class methods that get $context, already have their own
   Config and Logger instances injected from ResourceLoader::getModule(),
   which should be used instead.

Deprecating these opens the paths for making ResourceLoaderContext
a purer value object with no ResourceLoader, Config, or Logger objects
needing to be passed (in the future).

Bug: T32956
Change-Id: I74a9535918ea43b2c00073c5d4469f864d1eeb41