DOC: update the release howto for oldest-supported-numpy
DOC: update the release howto for oldest-supported-numpy

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mhvk/numpy,pdebuyl/numpy,mattip/numpy,pbrod/numpy,endolith/numpy,simongibbons/numpy,madphysicist/numpy,anntzer/numpy,seberg/numpy,rgommers/numpy,charris/numpy,mhvk/numpy,mattip/numpy,jakirkham/numpy,pdebuyl/numpy,mattip/numpy,simongibbons/numpy,pbrod/numpy,numpy/numpy,simongibbons/numpy,madphysicist/numpy,madphysicist/numpy,mhvk/numpy,charris/numpy,seberg/numpy,rgommers/numpy,mhvk/numpy,numpy/numpy,pdebuyl/numpy,seberg/numpy,rgommers/numpy,jakirkham/numpy,simongibbons/numpy,anntzer/numpy,charris/numpy,numpy/numpy,mhvk/numpy,jakirkham/numpy,madphysicist/numpy,mattip/numpy,pdebuyl/numpy,seberg/numpy,pbrod/numpy,endolith/numpy,charris/numpy,endolith/numpy,endolith/numpy,numpy/numpy,anntzer/numpy,madphysicist/numpy,simongibbons/numpy,pbrod/numpy,jakirkham/numpy,pbrod/numpy,anntzer/numpy,jakirkham/numpy,rgommers/numpy