modcluster:read-proxies-configuration throws IllegalArgumentException

Issue

• In some cases, the modcluster:read-proxies-configuration CLI command throws an IllegalArgumentException:

[standalone@localhost:9999 /] /subsystem=modcluster:read-proxies-configuration
{
    "outcome" => "failed",
    "result" => undefined,
    "failure-description" => "JBAS014749: Operation handler failed: java.lang.IllegalArgumentException: newValue is null",
    "rolled-back" => true
}