WorkflowStepConfig limit is the maximum number of retries, not attempts

### Existing documentation URL(s)

https://developers.cloudflare.com/workflows/build/sleeping-and-retrying/#retry-steps

### What changes are you suggesting?

The second **Retry steps** code sample is described as:
> to limit a step to 10 retries

but the code sample is:
```
retries: {
limit: 10, // The total number of attempts
```

These are contradictory: 10 retries means a total of 11 attempts. (Testing confirms that `retries.limit` is the maximum number of retries, not the maximum number of attempts.)

The code comment should be changed to:
```
retries: {
limit: 10, // The total number of retries (11 attempts total)
```

### Additional information

_No response_