[skip ci]Add util healthz comment (#9171)

Signed-off-by: godchen <qingxiang.chen@zilliz.com>

internal/util/healthz/content_type.go

@@ -12,6 +12,8 @@
 package healthz
 
 const (
+	// ContentTypeHeader is the health check request type header.
 	ContentTypeHeader = "Content-Type"
-	ContentTypeText   = "text/plain"
+	// ContentTypeHeader is the health check request type text.
+	ContentTypeText = "text/plain"
 )

internal/util/healthz/router.go

@@ -11,4 +11,5 @@
 
 package healthz
 
+// HealthzRouterPath is default path for check health state.
 const HealthzRouterPath = "/healthz"