Review NUnit1029

[atifaziz]

In PR #1023, updating the NUnit.Analyzers to version 3.8.0 introduced NUnit1029 warnings/errors:

A:\MoreLINQ\main\MoreLinq.Test\AggregateTest.cs(100,25,100,55): error NUnit1029: The TestCaseSource provides '1' parameter(s), but the Test method expects '2' parameter(s) (https://github.com/nunit/nunit.analyzers/tree/master/documentation/NUnit1029.md)
A:\MoreLINQ\main\MoreLinq.Test\ZipLongestTest.cs(46,31,46,47): error NUnit1029: The TestCaseSource provides '1' parameter(s), but the Test method expects '2' parameter(s) (https://github.com/nunit/nunit.analyzers/tree/master/documentation/NUnit1029.md)
A:\MoreLINQ\main\MoreLinq.Test\TrySingleTest.cs(58,25,58,61): error NUnit1029: The TestCaseSource provides '1' parameter(s), but the Test method expects '2' parameter(s) (https://github.com/nunit/nunit.analyzers/tree/master/documentation/NUnit1029.md)
A:\MoreLINQ\main\MoreLinq.Test\OrderedMergeTest.cs(65,31,65,47): error NUnit1029: The TestCaseSource provides '1' parameter(s), but the Test method expects '2' parameter(s) (https://github.com/nunit/nunit.analyzers/tree/master/documentation/NUnit1029.md)
A:\MoreLINQ\main\MoreLinq.Test\PrependTest.cs(61,25,61,50): error NUnit1029: The TestCaseSource provides '1' parameter(s), but the Test method expects '2' parameter(s) (https://github.com/nunit/nunit.analyzers/tree/master/documentation/NUnit1029.md)
A:\MoreLINQ\main\MoreLinq.Test\SkipUntilTest.cs(77,31,77,47): error NUnit1029: The TestCaseSource provides '1' parameter(s), but the Test method expects '2' parameter(s) (https://github.com/nunit/nunit.analyzers/tree/master/documentation/NUnit1029.md)

Since all tests pass regardless, the severity of NUnit1029 was demoted to suggestion:

https://github.com/morelinq/MoreLINQ/blob/91d3996df623934cf5a666bd34a4b039056aaa98/MoreLinq.Test/.editorconfig#L44-L45

It should be reviewed and ideally restored to a warning.