Update api comment about query parameter. (#2712)

* Update api comment about query parameter

* Make gen

Author: SpecialYang

networking/v1alpha3/virtual_service.pb.go

@@ -1100,11 +1100,12 @@ message HTTPMatchRequest {
   // - For a query parameter like "?key", the map key would be "key" and the
   //   string match could be defined as `exact: ""`.
   //
+  // - For a query parameter like "?key=abc" or "?key=abx", the map key would be "key" and the
+  //   string match could be defined as `prefix: "ab"`.
+  //
   // - For a query parameter like "?key=123", the map key would be "key" and the
   //   string match could be defined as `regex: "\d+$"`. Note that this
   //   configuration will only match values like "123" but not "a123" or "123a".
-  //
-  // **Note:** `prefix` matching is currently not supported.
   map<string, StringMatch> query_params = 9;
 
   // Flag to specify whether the URI matching should be case-insensitive.

networking/v1alpha3/virtual_service.pb.html

@@ -1100,11 +1100,12 @@ message HTTPMatchRequest {
   // - For a query parameter like "?key", the map key would be "key" and the
   //   string match could be defined as `exact: ""`.
   //
+  // - For a query parameter like "?key=abc" or "?key=abx", the map key would be "key" and the
+  //   string match could be defined as `prefix: "ab"`.
+  //
   // - For a query parameter like "?key=123", the map key would be "key" and the
   //   string match could be defined as `regex: "\d+$"`. Note that this
   //   configuration will only match values like "123" but not "a123" or "123a".
-  //
-  // **Note:** `prefix` matching is currently not supported.
   map<string, StringMatch> query_params = 9;
 
   // Flag to specify whether the URI matching should be case-insensitive.