Apply suggestions from code review

Signed-off-by: Viktor Söderqvist <viktor.soderqvist@est.tech>

src/sentinel.c

@@ -3746,7 +3746,7 @@ void sentinelCommand(client *c) {
             "    failover.",
             "CONFIG SET param value [param value ...]",
             "    Set a global Sentinel configuration parameter.",
-            "CONFIG GET <param> [param param ... param]",
+            "CONFIG GET param [param ...]",
             "    Get global Sentinel configuration parameter.",
             "DEBUG [<param> <value> ...]",
             "    Show a list of configurable time parameters and their values (milliseconds).",

tests/instances.tcl

@@ -538,7 +538,7 @@ proc end_tests {} {
 # The "S" command is used to interact with the N-th Sentinel.
 # The general form is:
 #
-# S <sentinel-id> command arg arg ... arg
+# S <sentinel-id> command arg [arg ...]
 #
 # Example to ping the Sentinel 0 (first instance): S 0 PING
 proc S {n args} {