Update deprecated checkout action to revision

.github/workflows/cmake.yml

@@ -15,7 +15,7 @@ jobs:
       fail-fast: false
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
       
     - name: Install ARM toolchain
       run: sudo apt-get install gcc-arm-none-eabi binutils-arm-none-eabi