[API Implementation]: Expose CookieException constructors

[deeprobin]

This PR implements and fixes #95965.

• Expose constructors
• Add doc comments
• Add new public API to ref assembly
• Add tests for passing null and non-null parameters to the ctors

Potentially breaking change if somebody does reflection hacks:

• Rename the previous internal parameter inner to innerException as defined in the approved API scheme.

Added APIs

namespace System.Net;

public partial class CookieException
{
    public CookieException(string? message);
    public CookieException(string? message, Exception? innerException);
 }

[dotnet-issue-labeler]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[dotnet-issue-labeler]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[campersau]

Suggested change

	Assert.Equal(inner, exception.InnerException);
	Assert.Same(inner, exception.InnerException);

[deeprobin]

There would be no difference in result, if I use Same.
Exception is an reference type with no Equals overload, so it already compares the reference.

https://sharplab.io/#v2:EYLgtghglgdgNAFxAJwK4wD4AEBMBGAWAChiA3CZAAgFMBHVCAGz0oF5KZqB3SgUQA8AxtQAOCKAHsYACgBEAQVkBKANxkKNekxxsO3PkNHipcxauLEseAJzSAJLN5bGISgG86DZm3aftAX2U1IitbBycvVzcAJWoAM2pkahhhCKYAZ2k/ZjhNLxwlQNUgA=

[MihaZupan]

Thanks

[MihaZupan]

Suggested change

	/// <remarks>
	/// The value of <paramref name="message"/> is stored in the <see cref="Exception.Message"/> property of the new instance.
	/// </remarks>

[MihaZupan]

Suggested change

	/// <param name="innerException">A nested <see cref="Exception"/>.</param>
	/// <param name="innerException">The exception that is the cause of the current exception.</param>

[MihaZupan]

Suggested change

	/// <remarks>
	/// The value of <paramref name="message"/> is stored in the <see cref="Exception.Message"/> property of the new instance.
	/// The value of <paramref name="message"/> is stored in the <see cref="Exception.InnerException"/> property of the new instance.
	/// </remarks>

[MihaZupan]

I think you'll have to include a reference to the new file in the test csproj.