replace deprecated nose dependency with pynose

replace deprecated nose dependency with pynose

after upgrading teuthology to centos 9 and python 3.10, the rgw
multisite test suite now fails to invoke nosetests with:

> AttributeError: module 'collections' has no attribute 'Callable'

this is a known issue tracked in https://github.com/nose-devs/nose/issues/1127

Shilpa found a new 'pynose' package which claims that:

> This version of nose is compatible with Python 3.7+ (including 3.13+).

replace the nose dependency that i initially added in
https://github.com/ceph/teuthology/pull/1069 with the current version
1.5.1 of pynose

to prepare this pr, i first changed setup.cfg then ran:

> ./update-requirements.sh -P "pynose==1.5.1"

Fixes: https://tracker.ceph.com/issues/66183
Signed-off-by: Casey Bodley <cbodley@redhat.com>