(#5654) Added emptyDir support to mount trait

[hernanDatgDev]

Handles: #5654

Currently there is no way to add an emptyDir volume without using a pod template. This is useful but using the pod template will override any volumes mounted when using the mount trait e.g. configmaps, secrets.
This PR adds the trait field mount.empty-dirs which uses the same syntax as the existing mount.volumes trait field. To add an emptyDir volume use:
trait=mount.empty-dirs=my-empty-dir:/var/test
📓 Note that the trait field empty-dirs will be translated to emptyDirs in the integration yaml (if using helm or working with yaml directly)

The example above will add the following to your integration yaml

spec:
  containers:
  - name: integration
    volumeMounts:
    - mountPath: /var/test
      name: my-empty-dir
  volumes:
  - emptyDir: {}
    name: my-empty-dir

Release Note

NONE

[hernanDatgDev]

Also I renamed the existing mount trait field mount.volumes to mount.persistent-volume-claims since it is accurate to what the operator is actually mounting, a persistent volume claim. This is to help avoid confusion and make a distinction clear for what type of volume was being mounted. This seemed important since I was adding support for another volume type.

[squakez]

LGTM but we need to revert a major API change introduced.

[squakez]

We cannot change this without a period of deprecation notice. This change affects the API specification, so, it must be reverted. It was an unfortunate choice when we created it as it really was meant to be PersistentVolumeClaims. We may think to change this when moving to a major API upgrade.

[squakez]

We should create a new test with empty dirs instead. So we test both the default (void) and the presence of the parameter.

[hernanDatgDev]

@squakez Made the appropriate changes and updated the test as well. Thanks for the feedback!