add undocumented prop instanceId to react-select (#15891)

types/react-select/index.d.ts

@@ -173,6 +173,11 @@ declare namespace ReactSelectClass {
          * renders a custom input
          */
         inputRenderer?: (props: Object) => React.ReactElement<any>;
+        /**
+         * allows for synchronization of component id's on server and client.
+         * @see https://github.com/JedWatson/react-select/pull/1105
+         */
+        instanceId?: string;
         /**
          * whether the Select is loading externally or not (such as options being loaded).
          * if true, a loading spinner will be shown at the right side.

types/react-select/react-select-tests.tsx

@@ -107,6 +107,7 @@ class SelectTest extends React.Component<React.Props<{}>, {}> {
             escapeClearsValue: true,
             filterOptions: filterOptions,
             ignoreAccents: true,
+            instanceId: 'custom-instance-id',
             joinValues: false,
             matchPos: "any",
             matchProp: "any",