fix: update buffer-layout to fix downstream bundler issues (#18529)

* fix: update buffer-layout to fix downstream bundler issues

* chore: run check on generated type declaration

web3.js/src/util/send-and-confirm-raw-transaction.ts

@@ -1,3 +1,5 @@
+import type {Buffer} from 'buffer';
+
 import {Connection} from '../connection';
 import type {TransactionSignature} from '../transaction';
 import type {ConfirmOptions} from '../connection';

web3.js/src/util/to-buffer.ts

@@ -1,7 +1,7 @@
 import {Buffer} from 'buffer';
 
 export const toBuffer = (arr: Buffer | Uint8Array | Array<number>): Buffer => {
-  if (arr instanceof Buffer) {
+  if (Buffer.isBuffer(arr)) {
     return arr;
   } else if (arr instanceof Uint8Array) {
     return Buffer.from(arr.buffer, arr.byteOffset, arr.byteLength);