test: address deprecation warning

fs.truncateSync() emits a deprecation warning when called with a file
descriptor. Move to fs.ftruncateSync().

PR-URL: #38448
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: Darshan Sen <[email protected]>
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Trivikram Kamat <[email protected]>

Author: Trott

test/pummel/test-fs-largefile.js

@@ -34,7 +34,7 @@ const fd = fs.openSync(filepath, 'w+');
 const offset = 5 * 1024 * 1024 * 1024; // 5GB
 const message = 'Large File';
 
-fs.truncateSync(fd, offset);
+fs.ftruncateSync(fd, offset);
 assert.strictEqual(fs.statSync(filepath).size, offset);
 const writeBuf = Buffer.from(message);
 fs.writeSync(fd, writeBuf, 0, writeBuf.length, offset);