audb searches for missing media when downloading a database without audio

[hagenw]

When donwloading a dataset without audio the first time audb looks for missing media, which shouldn't be the case.

You can reproduce the issue with:

db = audb.load("glaive-function-calling-v2", version="1.0.0", cache_root="./cache")

[hagenw]

We always look for missing files first when audb.load() is executed, see

audb/audb/core/load.py

Lines 735 to 741 in 13373bb

	missing_files = _missing_files(
	files,
	files_type,
	db_root,
	flavor,
	verbose,
	)

At the moment we do this for each file seperately. But we should change this and check first if the cache folder that should contain those files does exists already (make sure we do not create it before), and only check the single files if the folder exists.