Add warning/note info to the release notes (probably in the Deprecated section) to give a heads up to customers about the changing behavior of HOME/WORKDIR and that they will not be set by default on the Tasks starting from 1.6. The release note should also mention that in 1.6, admin can configure the OpenShift Pipelines operator to change the default behaviour to how it is in 1.5.

Slack Conversation: https://coreos.slack.com/archives/CG5GV6CJD/p1622709131248800