Remove warning log on module load

[mschwoer]

Move the warning that was issues on importing the tempmmap module to the first call of the associated methods, to avoid effects like this:

@jalew188 we could think implementing a similar mechanism for creating the actual TemporaryDirectory object, as importing this module has the side effect of always creating an (empty) temp folder.

[jalew188]

It shouldn't be warning I think. I think we can just logging.info or print(...).

Looks good to me

[mschwoer]

waiting for https://github.com/MannLabs/alphabase/pull/162 to be merged to avoid @sophiamaedler having to deal with potential merge conflict :-)