[CodeQL][SM03800] Remove unapproved usage of DSACryptoServiceProvider (dotnet#11540)

Fixes #
CodeQL SM03800 issue

Context
CodeQL is flagging unapproved usage of DSACryptoServiceProvider

Changes Made
The flagged code is not required in ClickOnce so deleting it.

Testing
ClickOnce signing scenarios validated from .NET Fx 3.5 through .NET 9.

Notes

Author: sujitnayak

src/Tasks/ManifestUtil/CngLightup.cs

@@ -26,7 +26,6 @@ namespace System.Security.Cryptography
 {
     internal static partial class CngLightup
     {
-        private const string DsaOid = "1.2.840.10040.4.1";
         private const string RsaOid = "1.2.840.113549.1.1.1";
 
         private const string HashAlgorithmNameTypeName = "System.Security.Cryptography.HashAlgorithmName";
@@ -57,9 +56,6 @@ internal static partial class CngLightup
 
         private static readonly Lazy<bool> s_preferRsaCng = new Lazy<bool>(DetectRsaCngSupport);
 
-        private static volatile Func<X509Certificate2, DSA> s_getDsaPublicKey;
-        private static volatile Func<X509Certificate2, DSA> s_getDsaPrivateKey;
-
         private static volatile Func<X509Certificate2, RSA> s_getRsaPublicKey;
         private static volatile Func<X509Certificate2, RSA> s_getRsaPrivateKey;
         private static volatile Func<RSA, byte[], string, byte[]> s_rsaPkcs1SignMethod;
@@ -112,30 +108,6 @@ internal static RSA GetRSAPrivateKey(X509Certificate2 cert)
             return s_getRsaPrivateKey(cert);
         }
 
-        internal static DSA GetDSAPublicKey(X509Certificate2 cert)
-        {
-            if (s_getDsaPublicKey == null)
-            {
-                s_getDsaPublicKey =
-                    BindCoreDelegate<DSA>("DSA", isPublic: true) ??
-                    BindGetCapiPublicKey<DSA, DSACryptoServiceProvider>(DsaOid);
-            }
-
-            return s_getDsaPublicKey(cert);
-        }
-
-        internal static DSA GetDSAPrivateKey(X509Certificate2 cert)
-        {
-            if (s_getDsaPrivateKey == null)
-            {
-                s_getDsaPrivateKey =
-                    BindCoreDelegate<DSA>("DSA", isPublic: false) ??
-                    BindGetCapiPrivateKey<DSA>(DsaOid, csp => new DSACryptoServiceProvider(csp));
-            }
-
-            return s_getDsaPrivateKey(cert);
-        }
-
 #if !CNG_LIGHTUP_NO_SYSTEM_CORE
         internal static ECDsa GetECDsaPublicKey(X509Certificate2 cert)
         {
@@ -526,7 +498,6 @@ private static Func<X509Certificate2, T> BindCoreDelegate<T>(string algorithmNam
             // Load System.Core.dll and load the appropriate extension class
             // (one of
             //    System.Security.Cryptography.X509Certificates.RSACertificateExtensions
-            //    System.Security.Cryptography.X509Certificates.DSACertificateExtensions
             //    System.Security.Cryptography.X509Certificates.ECDsaCertificateExtensions
             // )
             string typeName = "System.Security.Cryptography.X509Certificates." + algorithmName + "CertificateExtensions";
@@ -547,8 +518,6 @@ private static Func<X509Certificate2, T> BindCoreDelegate<T>(string algorithmNam
             // (one of
             //     GetRSAPublicKey(this X509Certificate2 c)
             //     GetRSAPrivateKey(this X509Certificate2 c)
-            //     GetDSAPublicKey(this X509Certificate2 c)
-            //     GetDSAPrivateKey(this X509Certificate2 c)
             //     GetECDsaPublicKey(this X509Certificate2 c)
             //     GetECDsaPrivateKey(this X509Certificate2 c)
             // )