Fix typo in upgrade docs

Author: technowhizz

doc/source/operations/upgrading-openstack.rst

@@ -207,7 +207,7 @@ to 3.12, then to 3.13 on Antelope before the Caracal upgrade. This upgrade
 should not cause an API outage (though it should still be considered "at
 risk").
 
-Some errors have been observed in testing when the upgrades are perfomed
+Some errors have been observed in testing when the upgrades are performed
 back-to-back. A 200s delay eliminates this issue. On particularly large or slow
 deployments, consider increasing this timeout.