`.pipe` causes zx to hang in 8.2.0

This file

```
import { $ } from 'zx';

await $`echo 1`.pipe(process.stdout);
console.log('2');
```

in zx 8.1.9:

```
$ yarn add zx@8.1.9 
$ bun run ./test.mts
1
2
$
```

in zx 8.2.0:

```
$ yarn add zx@8.2.0
$ bun run ./test.mts
1
<never returns to shell prompt>
```
