Re-enable xunit warning 2002 dotnet/corefx#39696 (dotnet/corefx#39706)

Re-enable xunit warning 2002 dotnet/corefx#39696 (dotnet/corefx#39706)

* Removed null checks on value types and enabled xunit 2002

* Updated Fill_OpenDataReader_Throws to use range check

Updated Fill_OpenDataReader_Throws to use range check for passing path

* Removed uneeded asserts and updated others

- Removed any assert for a valuetype where it was succeeded by a value type assertion (e.g. Assert.Equal(1, 1))
- Updated reflection tests to check flags for the specified scenario

* Update src/Microsoft.VisualBasic.Core/tests/FileSystemTests.cs

Co-Authored-By: Jeremy Barton <jbarton@microsoft.com>
* Update src/System.Reflection/tests/AssemblyNameTests.cs

Co-Authored-By: Jeremy Barton <jbarton@microsoft.com>
* Fixed failing reflection tests and removed Assert.NotNull for enum

* Pulled ruleset up from master to merge

* Cleaned up assert ordering for TestGuid

* Updated TestResponseWithoutContentEvents

- Asserted for 200 OK based on response from DefaultAzureServer + EmptyContentHandler

Commit migrated from https://github.com/dotnet/corefx/commit/c96e389f803b043753558878fefb575f3f85c934