beforeAll outside of describe increases the number of failed steps by 1

**Describe the bug**

Having a `beforeAll` outside any `describe`s leads to the test runner reporting an incorrect number of failed steps: one more than the actual number of tests that have failed.

**Steps to Reproduce**

`deno test` the script below:

```ts
import { assert } from '@std/assert';
import { describe, test, beforeAll } from '@std/testing/bdd';

beforeAll(() => {
// A `beforeAll` outside the `describe`, even empty, increases the number of failed tests by 1
});

describe('the describe', () => {
test('test 1', () => {
assert(Math.random() < 0.0001);
});
test('test 2', () => {
assert(Math.random() === 0.123456);
});
});
```

The output will include `FAILED | 0 passed | 1 failed (3 steps)`.

**Expected behavior**

The final test message should be `FAILED | 0 passed | 1 failed (2 steps)`.

**Environment**

- OS: Ubuntu 24.04
- deno version: 2.7.7
- jsr:@std/expect: 1.0.18
- jsr:@std/testing: 1.0.17

Start by running the provided `deno test` reproduction with `@std/testing/bdd` and confirm that two failed tests produce three steps. Trace the BDD runner's handling of a top-level `beforeAll`; done means the same reproduction reports `FAILED | 0 passed | 1 failed (2 steps)` without changing the behavior of failures inside `describe`.

Written by the indexing model from the issue text.