fix(prefer-called-exactly-once-with): check for toHaveBeenCalledOnce

[paescuj]

The prefer-called-exactly-once-with rule assumed that if two matchers for the same expect argument were found, they would be a toHaveBeenCalledOnce / toHaveBeenCalledWith pair:

expect(x).toHaveBeenCalledOnce();
expect(x).toHaveBeenCalledWith('hoge');

However, they might as well be two toHaveBeenCalledWith calls:

expect(x).toHaveBeenCalledWith('hoge');
expect(x).toHaveBeenCalledWith('foo');

In the latter case, the rule should not apply.

---

Under the assumption that this case is referred to in the issue, as other cases have already been covered (such as only one or more than 2 toHaveBeenCalledWith calls): Fixes #781

[veritem]

thanks