fix(firestore): remove discontinued v1beta1 declaration from types

Author: quirogas

handwritten/firestore/types/firestore.d.ts

@@ -3163,14 +3163,6 @@ declare namespace FirebaseFirestore {
      */
     build(): Buffer;
   }
-  /**
-   * The v1beta1 Veneer client. This client provides access to the underlying
-   * Firestore v1beta1 RPCs.
-   * @deprecated Prefer the v1 client instead of the v1beta1 client. If your use case requires the v1beta1 client, it is published as part of the standalone @google-cloud/firestore-api package.
-   */
-  export const v1beta1: {
-    FirestoreClient: typeof import('./v1beta1/firestore_client').FirestoreClient;
-  };
   /**
    * The v1 Veneer clients. These clients provide access to the Firestore Admin
    * API and the underlying Firestore v1 RPCs.