DEP: remove python-snappy and brotli as optional dependencies (no longer used)
See https://github.com/pandas-dev/pandas/issues/32417#issuecomment-1684356585 for context.

The `python-snappy` and `brotli` packages were in the past a dependency of fastparquet, but that is no longer the case (https://github.com/dask/fastparquet/commit/2e657224a7250d49aa2e4b8c457a98e008687c21, replaced by `cramjam` that provides both compression options). 
I am not sure if there was another reason that we included this in our optional dependencies, but I didn't find any other usage in our codebase. 

Closes #32417
thanks @jorisvandenbossche