Code cleanup and update public API interface

Author: MaggieKimani1

src/Microsoft.OpenApi/Models/OpenApiSecurityScheme.cs

@@ -318,9 +318,9 @@ private static void WriteOAuthFlowForV2(IOpenApiWriter writer, string flowValue,
         /// <param name="diagnostic"></param>
         /// <param name="settings"></param>
         /// <returns></returns>
-        public static OpenApiDiscriminator Load(string url, OpenApiSpecVersion version, out OpenApiDiagnostic diagnostic, OpenApiReaderSettings settings = null)
+        public static OpenApiSecurityScheme Load(string url, OpenApiSpecVersion version, out OpenApiDiagnostic diagnostic, OpenApiReaderSettings settings = null)
         {
-            return OpenApiModelFactory.Load<OpenApiDiscriminator>(url, version, out diagnostic, settings);
+            return OpenApiModelFactory.Load<OpenApiSecurityScheme>(url, version, out diagnostic, settings);
         }
 
         /// <summary>

test/Microsoft.OpenApi.Tests/PublicApi/PublicApi.approved.txt

@@ -1066,7 +1066,7 @@ namespace Microsoft.OpenApi.Models
         public virtual void SerializeAsV31(Microsoft.OpenApi.Writers.IOpenApiWriter writer) { }
         public virtual void SerializeAsV31WithoutReference(Microsoft.OpenApi.Writers.IOpenApiWriter writer) { }
         public virtual void SerializeAsV3WithoutReference(Microsoft.OpenApi.Writers.IOpenApiWriter writer) { }
-        public static Microsoft.OpenApi.Models.OpenApiDiscriminator Load(string url, Microsoft.OpenApi.OpenApiSpecVersion version, out Microsoft.OpenApi.Reader.OpenApiDiagnostic diagnostic, Microsoft.OpenApi.Reader.OpenApiReaderSettings settings = null) { }
+        public static Microsoft.OpenApi.Models.OpenApiSecurityScheme Load(string url, Microsoft.OpenApi.OpenApiSpecVersion version, out Microsoft.OpenApi.Reader.OpenApiDiagnostic diagnostic, Microsoft.OpenApi.Reader.OpenApiReaderSettings settings = null) { }
         public static Microsoft.OpenApi.Models.OpenApiSecurityScheme Load(System.IO.Stream stream, string format, Microsoft.OpenApi.OpenApiSpecVersion version, out Microsoft.OpenApi.Reader.OpenApiDiagnostic diagnostic, Microsoft.OpenApi.Reader.OpenApiReaderSettings settings = null) { }
         public static Microsoft.OpenApi.Models.OpenApiSecurityScheme Load(System.IO.TextReader input, string format, Microsoft.OpenApi.OpenApiSpecVersion version, out Microsoft.OpenApi.Reader.OpenApiDiagnostic diagnostic, Microsoft.OpenApi.Reader.OpenApiReaderSettings settings = null) { }
         public static Microsoft.OpenApi.Models.OpenApiSecurityScheme Parse(string input, Microsoft.OpenApi.OpenApiSpecVersion version, out Microsoft.OpenApi.Reader.OpenApiDiagnostic diagnostic, string format = null, Microsoft.OpenApi.Reader.OpenApiReaderSettings settings = null) { }