issue(object) {
        return Object.assign({
            issue_number: 
            // @ts-ignore - this.payload may not have `issue` or `pull_request` keys
            (this.payload.issue || this.payload.pull_request || this.payload)
                .number,
        }, this.repo(object));
    }
Return the `owner`, `repo`, and `issue_number` params for making API requests
against an issue. The object passed in will be merged with the repo params.


```js
const params = context.issue({body: 'Hello World!'})
// Returns: {owner: 'username', repo: 'reponame', issue_number: 123, body: 'Hello World!'}
```

@param object - Params to be merged with the issue params.