fix: support schema type inference based on schema options timestamps as well

[ark23CIS]

support schema type inference based on schema options timestamps as well

Fix #13215

Summary
Currently, InferSchemaType and InferRawDocType does not infer type based on timestamps fields provided in the schema options, which can lead to some difficulties while developing process (you'll have to add fields into your schema types manually to avoid the issue or extend returned typescript type).

[vkarpov15]

Thanks 👍