✨ Add CI for verifying whether the project is CMSIS Compliant (#4)

Introduce a CI flow to verify the project is compliant with CMSIS and
hence, could be used with the CMSIS toolbox

.github/workflows/verify.yml

@@ -0,0 +1,22 @@
+name: Verify CMSIS Compliance
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+  schedule:
+    - cron: '0 6 * * 2'
+
+jobs:
+  verify-cmsis-compliance:
+    name: Verify CMSIS Compliance
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: Arm-Examples/verify-cmsis-example-action@latest
+        name: Verify CMSIS Compliance
+        with:
+          branch: ${{ github.ref }}
+          project-file: ./Demo.csolution.yml
+          API_TOKEN: ${{ secrets.CMSIS_API_KEY }}

README.md

@@ -1,5 +1,6 @@
 AWS coreMQTT Mutual Authentication Demo
 =======================================
+[![CMSIS Compliance](https://img.shields.io/github/actions/workflow/status/Arm-Examples/AWS_MQTT_MutualAuth_Demo/verify.yml?logo=arm&logoColor=0091bd&label=CMSIS%20Compliance)](https://www.keil.arm.com/cmsis) 
 
 This demo application connects to **AWS MQTT broker** using TLS with mutual authentication between the client and the server.
 It demonstrates the subscribe-publish workflow of MQTT.