Fix GHRepository#listWorkflows() and add a test

[gsmet]

I don't know how I missed it but I forgot to add a test for listWorkflows() and... it didn't work properly.

I think we probably need a better infrastructure to deal with all these iterables to avoid having to add so many classes but that's something we can discuss another day :).

[bitwiseman]

Since this iterable only points to "actions/workflows" endpoint, you can late resolve the URL like we do here:

github-api/src/main/java/org/kohsuke/github/GHSearchBuilder.java

Lines 47 to 54 in 6caaf9e

	public PagedSearchIterable<T> list() {
	req.set("q", StringUtils.join(terms, " "));
	try {
	return new PagedSearchIterable<>(root, req.build(), receiverType);
	} catch (MalformedURLException e) {
	throw new GHException("", e);
	}

You can even pass only owner and create the requester in _iterator().

[gsmet]

I'm not entirely convinced given I find the current coding more consistent with the rest of the codebase but as you wish :).

[gsmet]

Done!

[bitwiseman]

Hm, yeah. Most other list* methods throw IOException. Since you made this method not throw IOException (which I like) I'd rather have that method really not throw.

It's probably silly, but thanks for being accommodating.

[bitwiseman]

Minor change suggested.