Refactor logic to accept a string as a regular param and rename the extension class

Author: MaggieKimani1

src/Microsoft.OpenApi.Hidi/OpenApiService.cs

@@ -22,7 +22,7 @@
 using Microsoft.OpenApi.Services;
 using Microsoft.OpenApi.Validations;
 using Microsoft.OpenApi.Writers;
-using static Microsoft.OpenApi.Hidi.OpenApiSpecVersionExtension;
+using static Microsoft.OpenApi.Hidi.OpenApiSpecVersionHelper;
 
 namespace Microsoft.OpenApi.Hidi
 {
@@ -91,7 +91,7 @@ string filterbycollection
             {
                 // Default to yaml and OpenApiVersion 3 during csdl to OpenApi conversion
                 openApiFormat = format ?? GetOpenApiFormat(csdl, logger);
-                openApiVersion = version.TryParseOpenApiSpecVersion();
+                openApiVersion = TryParseOpenApiSpecVersion(version);
 
                 stream = await GetStream(csdl, logger);
                 document = await ConvertCsdlToOpenApi(stream);

src/Microsoft.OpenApi.Hidi/OpenApiSpecVersionExtension.cs renamed to src/Microsoft.OpenApi.Hidi/OpenApiSpecVersionHelper.cs

@@ -6,24 +6,24 @@
 
 namespace Microsoft.OpenApi.Hidi
 {
-    public static class OpenApiSpecVersionExtension
+    public static class OpenApiSpecVersionHelper
     {
-        public static OpenApiSpecVersion TryParseOpenApiSpecVersion(this string value)
+        public static OpenApiSpecVersion TryParseOpenApiSpecVersion(string value)
         {
             if (string.IsNullOrEmpty(value))
             {
                 throw new InvalidOperationException("Please provide a version");
             }
             var res = value.Split('.', StringSplitOptions.RemoveEmptyEntries).FirstOrDefault();
-            
+
             if (int.TryParse(res, out int result))
             {
 
-                if (result >= 2 || result <= 3)
+                if (result >= 2 && result < 3)
                 {
-                    return (OpenApiSpecVersion)result;
+                    return OpenApiSpecVersion.OpenApi2_0;
                 }
-            }  
+            }
 
             return OpenApiSpecVersion.OpenApi3_0; // default
         }