Update checkout action version.

Author: kovacsv

.github/workflows/build.yml

@@ -15,7 +15,7 @@ jobs:
       fail-fast: false        
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Configure
       run: cmake -B ${{github.workspace}}/Build -DCMAKE_BUILD_TYPE=${{matrix.configuration}}
     - name: Build