Fix Typo LANGUAGE_FIELD->LANGUAGE in SerializeIndex (#458)

* Fix SerializeIndex

Fix type/bug in index serialization and creation which serializes `LanguageField` to `Language` instead of `Language_Field`

* adding author to readme

---------

Co-authored-by: slorello89 <steve.lorello@redis.com>

README.md

@@ -473,6 +473,7 @@ We'd love your contributions! If you want to contribute please read our [Contrib
 * [@abbottdev](https://github.com/abbottdev)
 * [@PrudiusVladislav](https://github.com/PrudiusVladislav)
 * [@CormacLennon](https://github.com/CormacLennon)
+* [@ahmedisam99](https://github.com/ahmedisam99)
 
 <!-- Logo -->
 [Logo]: images/logo.svg

src/Redis.OM/Modeling/RedisIndex.cs

@@ -77,7 +77,7 @@ internal static string[] SerializeIndex(this Type type)
 
             if (!string.IsNullOrEmpty(objAttribute.LanguageField))
             {
-                args.Add("LANGUAGE");
+                args.Add("LANGUAGE_FIELD");
                 args.Add(objAttribute.LanguageField!);
             }