update constraint for python-magnumclient to new release 4.8.1

meta: version: 4.8.1
meta: team: magnum
meta: diff-start: -
meta: series: epoxy
meta: branch: master
meta: release-type: release
meta: pypi: yes
meta: first: no
meta: release:Author: Előd Illés <elod.illes@est.tech>
meta: release:Commit: Előd Illés <elod.illes@est.tech>
meta: release:Change-Id: I8051be03f46ea76791fed5f016bda805b5bc912e
meta: release:Code-Review+2: Elod Illes <elod.illes@est.tech>
meta: release:Code-Review+2: Thierry Carrez <thierry@openstack.org>
meta: release:Code-Review+1: Dale Smith <dale@catalystcloud.nz>
meta: release:Workflow+1: Thierry Carrez <thierry@openstack.org>
Change-Id: If51dc75a38c8335f9e14286574d3569845855047

Author: OpenStack Proposal Bot

upper-constraints.txt

@@ -529,7 +529,7 @@ python-keystoneclient===5.6.0
 ceilometer===23.0.0
 diskimage-builder===3.37.0
 heat-translator===3.2.0
-python-magnumclient===4.8.0
+python-magnumclient===4.8.1
 docker===7.1.0
 storops===1.2.11
 anyio===4.8.0