Remove `raw_data_dimensions` from the Hyrax class

[drewoldag]

I believe that this method is a relic from the old times. I don't find anything when searching around for usage in the codebase.

I am not confident that we have alternative ways to get this information - but I also don't think that this is a method that makes sense to keep in the top-level class for the package.

[drewoldag]

Makes the most sense to mark this as deprecated. And bring this up a few times at the Hyrax Tech and Science meetings to make sure that poeple in Aritra's group know that it will be deprecated.