Lift off upper bound for MarkupSafe (#20113)

Per discussion and guidance from #19753, opening this PR for review. Based on if all the tests pass, this could be reviewed further. Resolves #19761.

setup.cfg

@@ -123,7 +123,7 @@ install_requires =
     lazy-object-proxy
     lockfile>=0.12.2
     markdown>=2.5.2, <4.0
-    markupsafe>=1.1.1, <=2.0
+    markupsafe>=1.1.1
     marshmallow-oneofschema>=2.0.1
     # Required by vendored-in connexion
     openapi-spec-validator>=0.2.4