Update Redis client (v9) and add TLS certificates

[Lajule]

Hi,

This PR contains an upgrade of the Redis client from v8 to v9 and some new config variables in order to specify TLS certificates (including CA) for the client.

Description

We use Redis 7.0.11 in cluster mode with TLS, to make Tyk works we add some config variables to provide TLS certificats to the TLSConfig of the Redis client in addition we have updated the client to the lasted version.

Related Issue

Could not connect to Redis in cluster mode with TLS

Motivation and Context

For security reasons we have to use TLS in every connections of ours infrastructure, that why we made this modifications

How This Has Been Tested

We build the container and test it directly in our test environment

Screenshots (if appropriate)

NA

Types of changes

• [ x] Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Refactoring or add test (improvements in base code or adds test coverage to functionality)

Checklist

• I ensured that the documentation is up to date
• I explained why this PR updates go.mod in detail with reasoning why it's required
• I would like a code coverage CI quality gate exception and have explained why

[titpetric]

It used to be that v9 had breaking changes in the redis protocol: there is still an issue open, redis/go-redis#2152 (comment) but it seems that RESP2 support has been added and the client promoted to official meanwhile.

The PR is a strong merge candidate now that we upgraded to 1.19 and can bump the dependency for redis, along with #4211. That PR contains updates that improve error returns and enable custom storage drivers.

Apart from removing log.Info around ping to not log the expected value, the changes are not objectionable. 👍😊

[titpetric]

@Lajule closed in error? The cert support imho is viable and we can include it. My comment was meant as your PR has value + the wip work has even more improvements. Happy to evaluate a merge here.

[Lajule]

I'll reopen one with certificates only,
Comming in few hours