Continuation of https://github.com/payloadcms/payload/pull/12265.
Currently, using `select` on new relationship virtual fields:
```
const doc = await payload.findByID({
collection: 'virtual-relations',
depth: 0,
id,
select: { postTitle: true },
})
```
doesn't work, because in order to calculate `post.title`, the `post`
field must be selected as well. This PR adds logic that sanitizes the
incoming `select` to include those relationships into `select` (that are
related to selected virtual fields)
---------
Co-authored-by: Dan Ribbens <dan.ribbens@gmail.com>
564fdb0e17