Add sync method to filehandle method

ext/node/polyfills/internal/fs/handle.ts

@@ -148,6 +148,10 @@ export class FileHandle extends EventEmitter {
   stat(options: { bigint: true }): Promise<BigIntStats>;
   stat(options?: { bigint: boolean }): Promise<Stats | BigIntStats> {
     return fsCall(promises.fstat, this, options);
+  };
+  // readLines(options?):Promise<InterfaceConstructor>
+  sync():Promise<void>{
+    return Promise.resolve(promises.sync());
   }
 }
 

tests/unit_node/_fs/_fs_handle_test.ts

@@ -70,6 +70,7 @@ Deno.test("[node/fs filehandle.write] Write from Buffer", async function () {
 
   const buffer = Buffer.from("hello world");
   const res = await fileHandle.write(buffer, 0, 5, 0);
+  await fileHandle.sync();
 
   const data = Deno.readFileSync(tempFile);
   await Deno.remove(tempFile);