[HTTP] Fix Content-Disposition name property getters

[ManickaP]

Now, GetName strips the quotes the same way as ASP.NET does in https://github.com/dotnet/aspnetcore/blob/87a766435f374abd674f7bb8dd60893daa1667cd/src/Http/Headers/src/ContentDispositionHeaderValue.cs#L423

Fixes #32765

[Copilot]

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (1)

src/libraries/System.Net.Http/src/System/Net/Http/Headers/ContentDispositionHeaderValue.cs:351

• Consider adding a guard for edge cases where nameParameter.Value may have a length less than 2 when quoted. This would help prevent potential runtime exceptions if an unexpected value is encountered.

return IsQuoted(nameParameter.Value) ? nameParameter.Value!.Substring(1, nameParameter.Value.Length - 2) : nameParameter.Value;