docs(guide+schematypes): add UUID to schematypes guide

[vkarpov15]

Fix #13032
Re: #13025

Summary

Add uuid to schematypes guide so we have some documentation to point to on how to work with uuids.

Examples

[hasezoey]

maybe also consider adding a note about mongoose.Types.UUID from #13186

also it would be good to note that not just uuid-v4 is supported, but all other versions and that mongoose does not do any checking that they are the same version (but does check that they match a pattern)

mongoose/lib/schema/uuid.js

Line 14 in 5b75e10

const UUID_FORMAT = /[0-9a-f]{8}-[0-9a-f]{4}-[0-9][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}/i;