Use latest release of StackHPC iDRAC role

This pulls in a number of fixes to the iDRAC role which includes
a change to allow the role to work with a recent version of the
python-dracclient library.

Change-Id: I6aa1fcece42f93cf404cf06dc96b2d70b140775e

releasenotes/notes/bugfix-update-idrac-role-71ede6900dc000a7.yaml

+---
+fixes:
+  - |
+    Fix an issue where the StackHPC iDRAC role would break when configuring
+    RAID when used with a recent release of the python-dracclient module.

requirements.yml

@@ -18,7 +18,7 @@
 - src: stackhpc.dell-powerconnect-switch
   version: v1.1.0
 - src: stackhpc.drac
-  version: 1.1.4
+  version: 1.1.5
 - src: stackhpc.drac-facts
   version: 1.0.0
 - src: stackhpc.grafana-conf