redis_enteprise : Redis v2 metrics upgrade

[j8-redis]

What does this PR do?

Redis have made numerous changes to their exported metrics. This pull request is for an updated integration that fully and completely understands those changes.

Motivation

We will be officially releasing the new metrics in the near future; we'd like the release of this integration to coincide.

Review checklist

• PR has a meaningful title or PR has the no-changelog label attached
• [X ] Feature or bugfix has tests
• [ X] Git history is clean
• If PR impacts documentation, docs team has been notified or an issue has been opened on the documentation repo
• If this PR includes a log pipeline, please add a description describing the remappers and processors.

Additional Notes

Anything else we should know when reviewing?