Add missing TlsAlertMessage members

[rzikm]

This would improve error messages in cases like #120257

    System.Net.Http.Functional.Tests.HttpClientHandlerTest_Http3.Public_Interop_ExactVersion_BufferContent_Success(uri: "https://quic.nginx.org/") [FAIL]
      System.Net.Http.HttpRequestException : Authentication failed because the remote party sent a TLS alert: '112'. (quic.nginx.org:443)
      ---- System.Security.Authentication.AuthenticationException : Authentication failed because the remote party sent a TLS alert: '112'.

After this PR, it would read TLS alert 'UnrecognizedName'.

[Copilot]

Pull Request Overview

This PR enhances TLS alert message handling by adding missing alert types and fixing enum naming inconsistencies. The changes improve error message clarity by providing meaningful alert names instead of numeric codes.

Key changes:

• Added 12 missing TLS alert message enum values including commonly encountered alerts like UnrecognizedName and CertificateRequired
• Fixed spelling inconsistencies in enum names (InsuffientSecurity → InsufficientSecurity, UnsupportedExt → UnsupportedExtension)
• Updated corresponding unit tests to use the corrected enum names

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/libraries/Common/src/System/Net/Security/TlsAlertMessage.cs	Added missing TLS alert enum values and fixed spelling in existing enum names
src/libraries/System.Net.Security/tests/UnitTests/TlsAlertsMatchWindowsInterop.cs	Updated test assertions to use corrected enum names

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[rzikm]

/ba-g System.Security.Cryptography.Tests.WorkItemExecution failure is unrelated