docs: update changelog for v2.1.0

Author: maureenorea-clores

README.md

@@ -225,7 +225,7 @@ val retrofit = Retrofit.Builder().build("your_baseUrl", okHttpClient gsonConvert
 
 ## Changelog
 
-### v2.1.0 (In-Progress)
+### v2.1.0 (2022-08-02)
 * SDKCF-5307: Added version string resource which can be referenced by the name `sdk_utils__version`.
 * SDKCF-4921: Added support for building with Java 11.