Include "outputs.publish-date"

[fallemand]

It will be important to know how "old" is the new version.
In many cases, we don't want to merge very fresh dependencies, and we wish to delay it for some time.

[jeffwidman]

Seems reasonable in theory to me... not sure how easy it is to get at that data, you'd probably have to modify core as well, but if you put together a PR I'd happily review it.

Related:

• Configuration of a minimum package age required before a PR is created dependabot-core#3651