Pin setuptools<71 for coffea 0.7.x

[oshadura]

Fixes broken tests from PR #32:

2024-09-24 12:10:40,298 - distributed.worker - ERROR - Compute Failed
Key:       MyProcessor-b3328515488d1f102eb8845099c03df1
State:     executing
Function:  MyProcessor
args:      ((WorkItem(dataset='dimuon', filename='https://github.com/CoffeaTeam/coffea/raw/master/tests/samples/nano_dimuon.root', treename='Events', entrystart=0, entrystop=40, fileuuid=b'\xa2\x10\xa3\xf86H\x11\xea\xa2\x9f\xf5\xb5\\\x90\xbe\xef', usermeta={}), b'\x04"M\x18h@-\x00\x00\x00\x00\x00\x00\x00v,\x00\x00\x00R\x80\x05\x95"\x00\x01\x00\xf0\x13\x8c\x0btest_dimuon\x94\x8c\x0bMyProcessor\x94\x93\x94)\x81\x94.\x00\x00\x00\x00'))
kwargs:    {}
Exception: 'AttributeError("module \'setuptools\' has no attribute \'extern\'")'

and the same issue which was reported scikit-hep/uproot5#1259