Remove `Volume.load` dtype FINNUFT workaround

[j-c-c]

There is currently a workaround to the finnuft dtype bug in Volume.load:

ASPIRE-Python/src/aspire/volume/volume.py

Lines 542 to 546 in a37d6ee

	# FINUFFT work around
	if loaded_data.dtype == np.float32:
	loaded_data = loaded_data.astype(np.float32)
	elif loaded_data.dtype == np.float64:
	loaded_data = loaded_data.astype(np.float64)

This will need to be removed after the next finnuft release.

[garrettwrong]

Resolved by #1168