Fix typo in index.d.ts (#441)

Co-authored-by: Sindre Sorhus <[email protected]>

Author: wibjorn

index.d.ts

@@ -432,9 +432,15 @@ declare const execa: {
 		console.log(stdout);
 		//=> 'unicorns'
 
+
 		// Cancelling a spawned process
+
 		const subprocess = execa('node');
-		setTimeout(() => { spawned.cancel() }, 1000);
+
+		setTimeout(() => {
+			subprocess.cancel()
+		}, 1000);
+
 		try {
 			await subprocess;
 		} catch (error) {