Optimize Batch for empty IReadOnlyCollection<T> too

[leandromoh]

No description provided.

[fsateler]

I think we should have tests for this optimization, but I don't think there was one for IReadOnlyList previously.

CI failure looks unrelated

[fsateler]

We should add tests for this

[codecov]

Codecov Report

Merging #750 into master will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #750   +/-   ##
=======================================
  Coverage   93.03%   93.03%           
=======================================
  Files         106      106           
  Lines        3473     3473           
=======================================
  Hits         3231     3231           
  Misses        242      242           

Impacted Files	Coverage Δ
MoreLinq/Batch.cs	100.00% <100.00%> (ø)

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[atifaziz]

I agree with @fsateler's comment that a test should have been added.

but I don't think there was one for IReadOnlyList previously.

@fsateler There was one on line 123:

MoreLINQ/MoreLinq.Test/BatchTest.cs

Lines 121 to 129 in d567555

	[TestCase(SourceKind.Sequence)]
	[TestCase(SourceKind.BreakingList)]
	[TestCase(SourceKind.BreakingReadOnlyList)]
	[TestCase(SourceKind.BreakingCollection)]
	public void BatchEmptySource(SourceKind kind)
	{
	var batches = Enumerable.Empty<int>().ToSourceKind(kind).Batch(100);
	Assert.That(batches, Is.Empty);
	}

Anyway, it was super quick to add another case so I went ahead and did it with e3cfba1.

@leandromoh Thanks for this PR!

@fsateler Thanks for your review.

[leandromoh]

thank you both!

@atifaziz Merging is showing blocked for me. May you merge?