feat: implement redis cluster ready state

[drivebyer]

Description

When we got ready state, the redis cluster should be healthy.

Type of change

• New feature (non-breaking change which adds functionality)

Checklist

• [x] Tests have been added/modified and all tests pass.
• [x] Functionality/bugs have been confirmed to be unchanged or fixed.
• [x] I have performed a self-review of my own code.
• [ ] Documentation has been updated or added where necessary.

Additional Context

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 33 lines in your changes are missing coverage. Please review.

Project coverage is 38.34%. Comparing base (d121d86) to head (024835f). Report is 22 commits behind head on master.

Files	Patch %	Lines
k8sutils/redis.go	0.00%	28 Missing :warning:
controllers/rediscluster_controller.go	0.00%	5 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #867 +/- ## ========================================== + Coverage 35.20% 38.34% +3.14% ========================================== Files 19 19 Lines 3213 2655 -558 ========================================== - Hits 1131 1018 -113 + Misses 2015 1569 -446 - Partials 67 68 +1 ```

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