[DOCS]: github_repository_webhook provides wrong import command

### Describe the need

[Import command](https://registry.terraform.io/providers/integrations/github/latest/docs/resources/repository_webhook.html#import) for github_repository_webhook is wrongly described.

It says
```
$ terraform import github_repository_webhook.terraform terraform/11235813
```

While it has to be
```
$ terraform import github_repository_webhook.terraform foo-repo/11235813
```

### SDK Version

_No response_

### API Version

_No response_

### Relevant log output

```shell

```

### Code of Conduct

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