Fix error message for sl (steam locomotive)

When running jest in watch mode, with `sl` installed
(https://github.com/mtoyoda/sl), it errors out with the following
message:

```
  ● Test suite failed to run

thrown: [Error]
```

This is bad because the error is extremely hard to debug.

This change makes it error as follows:

```
  ● Test suite failed to run

    Command failed with ENAMETOOLONG: sl status -amnu /Users/rmartine/dev/ias-backstage/packages/backend
    spawn ENAMETOOLONG
```

This, at least, points people in the right direction.

See also: jestjs#14046

packages/jest-changed-files/src/sl.ts

@@ -7,7 +7,6 @@
  */
 
 import * as path from 'path';
-import {types} from 'util';
 import execa = require('execa');
 import type {SCMAdapter} from './types';
 
@@ -34,19 +33,7 @@ const adapter: SCMAdapter = {
     }
     args.push(...includePaths);
 
-    let result: execa.ExecaReturnValue;
-
-    try {
-      result = await execa('sl', args, {cwd, env});
-    } catch (error) {
-      if (types.isNativeError(error)) {
-        const err = error as execa.ExecaError;
-        // TODO: Should we keep the original `message`?
-        err.message = err.stderr;
-      }
-
-      throw error;
-    }
+    const result = await execa('sl', args, {cwd, env});
 
     return result.stdout
       .split('\n')