TST: Fixup slow metadata promotion tests to match new behaviour
TST: Fixup slow metadata promotion tests to match new behaviour

pdebuyl/numpy,rgommers/numpy,pdebuyl/numpy,mattip/numpy,anntzer/numpy,numpy/numpy,pdebuyl/numpy,anntzer/numpy,anntzer/numpy,endolith/numpy,endolith/numpy,charris/numpy,charris/numpy,rgommers/numpy,endolith/numpy,anntzer/numpy,rgommers/numpy,charris/numpy,endolith/numpy,numpy/numpy,mhvk/numpy,mattip/numpy,mhvk/numpy,pdebuyl/numpy,rgommers/numpy,mhvk/numpy,mhvk/numpy,mattip/numpy,charris/numpy,mhvk/numpy,numpy/numpy,numpy/numpy,mattip/numpy