Allow build info goal's timestamp to be disabled so that its output is repeatable

[oehme]

The build-info goal injects a timestamp into the build output and there is no way to suppress that as far as I can tell. In the spirit of reproducible builds, it would be great if this could be deactivated.

[wilkinsona]

Thanks for the suggestion. This would align the Maven plugin's capabilities with our Gradle plugin. It was originally done in Gradle for up-to-date checking purposes but since c802180 it now makes things reproducible too.

[philwebb]

Closing in favor of PR #17390