Change to single stage build

[RobGeada]

Description

To enable Konflux builds, the Dockerfile has been changed to a single stage build. As far as I can tell, this does not change the size of the produced artifact, it is ~6GB in both the single and multi-stage format.

How Has This Been Tested?

Merge criteria:

• [ ] The commits are squashed in a cohesive manner and have meaningful messages.
• [ ] Testing instructions have been added in the PR body (for PRs involving changes that are not immediately obvious).
• [ ] The developer has manually tested the changes and verified that the changes work

[openshift-ci[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: RobGeada

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