check for known-slave in sentinel rewrite config (#11775)

Fix the following config file error

```
*** FATAL CONFIG FILE ERROR (Redis 6.2.7) ***
Reading the configuration file, at line 152
>>> 'sentinel known-replica XXXX 127.0.0.1 5001'
Duplicate hostname and port for replica.
```


that is happening when a user uses the legacy key "known-slave" in
the config file and a config rewrite occurs. The config rewrite logic won't
replace the old  line "sentinel known-slave XXXX 127.0.0.1 5001" and
would add a new line with "sentinel known-replica XXXX 127.0.0.1 5001"
which results in the error above "Duplicate hostname and port for replica."

example:

Current sentinal.conf
```
...

sentinel known-slave XXXX 127.0.0.1 5001
sentinel example-random-option X
...
```
after the config rewrite logic runs:
```
....
sentinel known-slave XXXX 127.0.0.1 5001
sentinel example-random-option X

# Generated by CONFIG REWRITE
sentinel known-replica XXXX 127.0.0.1 5001
```

This bug only exists in Redis versions >=6.2 because prior to that it was hidden
by the effects of this bug https://github.com/redis/redis/issues/5388 that was fixed
in https://github.com/redis/redis/pull/8271 and was released in versions >=6.2

0 files changed, 0 insertions, 0 deletions