Don't expose java info contributor by default

[philwebb]

See #28136 (comment)

We're going to flip the default so it's not exposed by default.

[dominikbrandon]

Would you mind sharing a hint on how to do that? This issue seemed easy to me, so I thought I'd help you with that, but I just can't find any way to set the default management.info.java.enabled value.

[wilkinsona]

Thanks for taking a look. We're not yet sure how to handle this one. We could perhaps flip the default for all info contributors or we may need to introduce a new attribute on the @ConditionalOnEnabledInfoContributor so that we can indicate that the Java info contributor should be disabled by default. I'll flag this for team meeting so that we can consider our options.