feat(manufacturers): update the API

#### manufacturers:v1

The following keys were added:
- schemas.Attributes.properties.sizeType.items.type

The following keys were changed:
- schemas.Attributes.properties.sizeType.type

discovery/manufacturers-v1.json

@@ -287,7 +287,7 @@
       }
     }
   },
-  "revision": "20210303",
+  "revision": "20210512",
   "rootUrl": "https://manufacturers.googleapis.com/",
   "schemas": {
     "Attributes": {
@@ -447,7 +447,10 @@
         },
         "sizeType": {
           "description": "The size type of the product. For more information, see https://support.google.com/manufacturers/answer/6124116#sizetype.",
-          "type": "string"
+          "items": {
+            "type": "string"
+          },
+          "type": "array"
         },
         "suggestedRetailPrice": {
           "$ref": "Price",

src/apis/manufacturers/v1.ts

@@ -256,7 +256,7 @@ export namespace manufacturers_v1 {
     /**
      * The size type of the product. For more information, see https://support.google.com/manufacturers/answer/6124116#sizetype.
      */
-    sizeType?: string | null;
+    sizeType?: string[] | null;
     /**
      * The suggested retail price (MSRP) of the product. For more information, see https://support.google.com/manufacturers/answer/6124116#price.
      */
@@ -965,7 +965,7 @@ export namespace manufacturers_v1 {
      *       //   "scent": "my_scent",
      *       //   "size": "my_size",
      *       //   "sizeSystem": "my_sizeSystem",
-     *       //   "sizeType": "my_sizeType",
+     *       //   "sizeType": [],
      *       //   "suggestedRetailPrice": {},
      *       //   "targetClientId": "my_targetClientId",
      *       //   "theme": "my_theme",