fence_compute fails with error "Nova not found or not accessible" in an OSP Pacemaker cluster

Issue

• A fence_compute stonith device failed during an upgrade from OSP13 to OSP16 with the following errors:

  Jul 15 12:44:37 controller-0 /fence_compute[404909]: Nova not found or not accessible
  Jul 15 12:44:37 controller-0 /fence_compute[404909]: Please use '-h' for usage
  

• /var/log/pacemaker/pacemaker.log shows the following error

  # less /var/log/pacemaker/pacemaker.log
  
  Jan 01 01:18:38.738 controller-0 pacemaker-fenced    [1234] (log_action)   warning: fence_compute[1234] stderr: [ 2025-01-01 01:18:38,719 ERROR: Nova not found or not accessible ]
  Jan 01 01:18:38.738 controller-0 pacemaker-fenced    [1234] (log_action)   warning: fence_compute[1234] stderr: [  ]
  Jan 01 01:18:38.738 controller-0 pacemaker-fenced    [1234] (log_action)   warning: fence_compute[1234] stderr: [ 2025-01-01 01:18:38,719 ERROR: Please use '-h' for usage ]
  Jan 01 01:18:38.738 controller-0 pacemaker-fenced    [1234] (log_action)   warning: fence_compute[1234] stderr: [  ]