Use up-to-date releases of Redis for CI workflow

[atakavci]

This PR is to update the Redis versions running in the CI, there are two different test setups according to environments, one on Ubuntu and the other on Windows;

• Ubuntu job is now using docker image with latest Redis release, it was using a relatively up-to-date version (7.4-rc1 -> 7.4.2)
• Windows job was using the binaries of an old version of Redis which was build to run on Windows env, but it is quite old(Redis 3.0.503) and lack of a set of features/changes that StackExchange.Redis already capable of when running with up-to-date Redis versions. So this is replaced with the Redis 7.4.2 which is the latest GA Release(as of now) in package repository.
  Setup for Windows essentially leverages wsl setup on windows and install+run the version of Redis from its own package repository. The rest is similar to existing approach, using the same config files etc..

[NickCraver]

@atakavci I have been checking on our ability to run Redis in Docker from Windows agents and did not realize it had finally happened. This is awesome. I need to find time to get the test suite reliably stable, that's the main thing standing in the way a lot of days, but this looks great. Trying to get a minor release out for a known cluster issue then will get this in.

[atakavci]

hey @NickCraver , any updates with this one ? please let me know if you have any concern..

[mgravell]

LGTM, but I'm trying to see if I can poke the CI; a CI change with red CI is ... #awkward - but: the CI has been getting flakier lately; needs some love

[mgravell]

(CI was refusing to rerun, presumably too old; I pushed an empty commit to see if we can poke it)