defaults.publishIvy = false not working always

[ljacomet]

When configuring defaults to skip ivy.xml publication, the setting is ignored the moment a repository Ivy layout is configured.

This is because the test in this part will always be false as the publisher will reply true because of this code.

If this is the expected behavior, because setting an Ivy repo layout overrides the defaults, then documentation should be adapted.
If this is not the expected behavior, then the logic needs to be changed. However comments linking to detection of CI environment makes me wonder what would be the correct behavior for all cases.