Attempt publishing docker images only if PUBLISH_DOCKER_IMAGE_ENABLED variable is set to true

[woj-tek]

This PR tries to resolve this issue: #2714. It would build the docker images but will try pushing them only if repository action variable PUBLISH_DOCKER_IMAGE_ENABLED is set to true

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• I have tested my changes
• There is no breaking changes
• I really tested my changes and there is no regression
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[fguillot]

Can you please rename PUBLISH_DOCKER_IMAGE_ENABLED to PUBLISH_DOCKER_IMAGES? Seems better to me

[woj-tek]

Renamed.

[woj-tek]

Thank you for merging!