Openshift does not support using nested mount points when mounting volumes - as discussed in bug - https://issues.redhat.com/browse/OCPBUGS-44667

A nested mount point is a mount point, which attempts to use a mount point created by previous volume. Such that:

        - mountPath: /opt/ibm/wlp/output
          name: output-folder-pvc
.....

        - mountPath: /opt/ibm/wlp/output/defaultServer/resources/security/keystore/pkcs12/server.p12
          name: key-trust-store
          subPath: keystore/pkcs12/server.p12 

Since We do not guarantee order in which mount points get created, such usage is prone to race conditions and undefined behaviour.