health check: add Redis custom health checker (#2993)

Signed-off-by: Dhi Aurrahman <dio@rockybars.com>

Mirrored from https://github.com/envoyproxy/envoy @ f467be38b0876633fb72ee6ffd70b122bbc728c9

envoy/api/v2/core/health_check.proto

@@ -116,9 +116,9 @@ message HealthCheck {
     string service_name = 1;
   }
 
-  // [#not-implemented-hide:] Custom health check.
+  // Custom health check.
   message CustomHealthCheck {
-    // The registered name of the custom health check.
+    // The registered name of the custom health checker.
     string name = 1 [(validate.rules).string.min_bytes = 1];
 
     // A custom health checker specific configuration which depends on the custom health checker
@@ -141,7 +141,7 @@ message HealthCheck {
     // gRPC health check.
     GrpcHealthCheck grpc_health_check = 11;
 
-    // [#not-implemented-hide:] Custom health check.
+    // Custom health check.
     CustomHealthCheck custom_health_check = 13;
   }
 

envoy/config/health_checker/redis/v2/redis.proto

@@ -3,10 +3,9 @@ syntax = "proto3";
 package envoy.config.health_checker.redis.v2;
 option go_package = "v2";
 
-// [#not-implemented-hide:]
 // [#protodoc-title: Redis]
-// Redis :ref:`configuration overview <config_health_checker_redis>`.
+// Redis health checker :ref:`configuration overview <config_health_checkers_redis>`.
-// Configuration for the Redis custom health checker.
+
 message Redis {
   // If set, optionally perform ``EXISTS <key>`` instead of ``PING``. A return value
   // from Redis of 0 (does not exist) is considered a passing healthcheck. A return value other