Update minimum requirements for ilo drivers

The proliantutils version needed is updated to 2.13.0
When running tests with older versions we get the error:
AttributeError: None does not have the attribute 'IloClient'

Change-Id: I6ab0672679c9d929c1e7c43a5966e6ad1e5353c0
Co-Authored-By: Thomas Goirand <thomas@goirand.fr>

driver-requirements.txt

@@ -4,7 +4,7 @@
 # python projects they should package as optional dependencies for Ironic.
 
 # These are available on pypi
-proliantutils>=2.11.0
+proliantutils>=2.13.0
 pysnmp>=4.3.0,<5.0.0
 python-scciclient>=0.8.0
 python-dracclient>=5.1.0,<9.0.0