fix(cloudsearch): update the API

#### cloudsearch:v1
The following keys were changed:
- schemas.SearchRequest.properties.pageSize.description

discovery/cloudsearch-v1.json

@@ -1870,7 +1870,7 @@
       }
     }
   },
-  "revision": "20200905",
+  "revision": "20200929",
   "rootUrl": "https://cloudsearch.googleapis.com/",
   "schemas": {
     "BooleanOperatorOptions": {
@@ -4456,7 +4456,7 @@
           "type": "array"
         },
         "pageSize": {
-          "description": "Maximum number of search results to return in one page. Valid values are between 1 and 100, inclusive. Default value is 10.",
+          "description": "Maximum number of search results to return in one page. Valid values are between 1 and 100, inclusive. Default value is 10. Minimum value is 50 when results beyond 2000 are requested.",
           "format": "int32",
           "type": "integer"
         },

src/apis/cloudsearch/v1.ts

@@ -1743,7 +1743,7 @@ export namespace cloudsearch_v1 {
     dataSourceRestrictions?: Schema$DataSourceRestriction[];
     facetOptions?: Schema$FacetOptions[];
     /**
-     * Maximum number of search results to return in one page. Valid values are between 1 and 100, inclusive. Default value is 10.
+     * Maximum number of search results to return in one page. Valid values are between 1 and 100, inclusive. Default value is 10. Minimum value is 50 when results beyond 2000 are requested.
      */
     pageSize?: number | null;
     /**