RFC: Remove Publish Date

Adding the [`Accept: application/vnd.npm.install-v1+json`](https://github.com/npm/registry/blob/master/docs/responses/package-metadata.md) header to the request to npm can drop the response time from 1500ms down to 700ms, however this does not include the publish date in the response. The performance difference is particularly noticeable for packages with a lot of versions, such as [`next`](https://packagephobia.com/result?p=next@14.0.3). Since we didn't show publish date until PR #460, and I'm wondering if we can just remove it in favor of performance. @XhmikosR Thoughts?