Update caching documentation for usage of Keyv with CacheModule

[nickhall]

I'm submitting a...

• Regression
• Bug report
• Feature request
• Documentation issue or request (new chapter/page)
• Support request => Please do not submit support request here, instead post your question on Stack Overflow.

Current behavior

https://docs.nestjs.com/techniques/caching#different-stores

In order to use different stores with the CacheModule, the docs say to use the cache-manager package with cache-manager-redis-yet

https://www.npmjs.com/package/cache-manager-redis-yet

If you check this package, though, you'll notice that the package has a deprecation message:

This package has been deprecated
Author message:
With cache-manager v6 we now are using Keyv

On top of that, cache-manager is now cacheable, and they seem to be moving to a new package: https://github.com/jaredwray/cacheable

I would like to avoid using deprecated packages, but it's unclear how to use Keyv to set up the cache. The Keyv project site has a tutorial about setting it up to work with Nest, but this does not integrate with the CacheModule system and loses the included benefits.

Expected behavior

I would like to see the docs updated with official guidance around how to integrate with external cache providers

What is the motivation / use case for changing the behavior?

This should make it easy for people who are new Nest to set up basic functionality.