[core] Redact redis password in log (#50409)

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## Why are these changes needed?
This change is needed to prevent redis password been logged in the
standard logging. This is a secure vulnerability.

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solves. -->

## Related issue number

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Closes #50266

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---------

Signed-off-by: Letao Jiang <[email protected]>
Signed-off-by: Philipp Moritz <[email protected]>
Co-authored-by: Philipp Moritz <[email protected]>

python/ray/util/client/server/server.py

@@ -892,7 +892,10 @@ def main():
     )
 
     hostport = "%s:%d" % (args.host, args.port)
-    logger.info(f"Starting Ray Client server on {hostport}, args {args}")
+    args_str = str(args)
+    if args.redis_password:
+        args_str = args_str.replace(args.redis_password, "****")
+    logger.info(f"Starting Ray Client server on {hostport}, args {args_str}")
     if args.mode == "proxy":
         server = serve_proxier(
             hostport,