test: change function to write to file

Co-authored-by: Darshan Sen <[email protected]>

Author: emilsivervik

test/parallel/test-fs-promises-file-handle-readFile.js

@@ -97,8 +97,7 @@ async function doReadAndCancel() {
     const kIoMaxLength = 2 ** 31 - 1;
 
     const newFile = path.resolve(tmpDir, 'dogs-running3.txt');
-    const buffer = Buffer.alloc(kIoMaxLength + 1);
-    await writeFile(newFile, buffer);
+    await truncate(newFile, kIoMaxLength + 1);
 
     const fileHandle = await open(newFile, 'r');