TST: drastically reduce the number of data sizes in the tests, to avoid an overly long test duration.
TST: drastically reduce the number of data sizes in the tests, to avoid an overly long test duration.

credit for this change goes to ThomasA who pointed out the long durations and suggested reducing the
number of sizes tested.

eriol/pywt,rgommers/pywt,aaren/pywt,PyWavelets/pywt,ThomasA/pywt,aaren/pywt,michelp/pywt,eriol/pywt,grlee77/pywt,grlee77/pywt,rgommers/pywt,michelp/pywt,PyWavelets/pywt,ThomasA/pywt,michelp/pywt,ThomasA/pywt,kwohlfahrt/pywt,aaren/pywt,kwohlfahrt/pywt,kwohlfahrt/pywt,rgommers/pywt,eriol/pywt,rgommers/pywt