Introduced Github Status Badge for Unit Tests (#634)

* Introduced Github Status Badge for Unit Tests

* Github status badge to point to latest run

* Github status badge UT points to latest results

* Fixed URL for Github Status badge

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Co-authored-by: kar-rahul-aws <118818625+kar-rahul-aws@users.noreply.github.com>

README.md

@@ -1,3 +1,5 @@
+[![CMock Unit Tests](https://github.com/FreeRTOS/FreeRTOS-Kernel/actions/workflows/unit-tests.yml/badge.svg?branch=main&event=push)](https://github.com/FreeRTOS/FreeRTOS-Kernel/actions/workflows/unit-tests.yml?query=branch%3Amain+event%3Apush+workflow%3A%22CMock+Unit+Tests%22++)
+
 ## Getting started
 This repository contains FreeRTOS kernel source/header files and kernel ports only. This repository is referenced as a submodule in [FreeRTOS/FreeRTOS](https://github.com/FreeRTOS/FreeRTOS) repository, which contains pre-configured demo application projects under ```FreeRTOS/Demo``` directory.