FIX: correct pytest assertion
FIX: correct pytest assertion

Signed-off-by: Kai Muehlbauer <06809f38505a7ac2c0f511e47d8d15c86fc98e7c@wradlib.org>

kmuehlbauer/wradlib,heistermann/wradlib,wradlib/wradlib,heistermann/wradlib,wradlib/wradlib,kmuehlbauer/wradlib