Remove Deploy to OpenShift file from downstreamdoc.yaml file

[sheilamjones]

Due to change in scope for 3.2, the upstream "Deploy to OpenShift" guides will not be published in Red Hat build of Quarkus for 3.2. Therefore, the OpenShift-specific files do not need to be imported downstream for 3.2.

This PR covers the update of the "downstreamdoc.yaml" file to remove the "deploying-to-openshift.adoc " file from the list of needed downstream files.

[sheilamjones]

Hi @gsmet,
Per change in scope outlined last week in relation to the upstream Deploy to OpenShift content, whereby the upstream content will no longer be published in RHBQ for 3.2, the "deploying-to-openshift.adoc" file is no longer required in the downsteam repository for 3.2. I updated the downstreamdoc.yaml file to remove it from the list and would appreciate your review.
Many thanks,
Sheila