Update CI

Author: whaeck

.github/workflows/ContinuousIntegration.yml

@@ -17,15 +17,15 @@ jobs:
     strategy:
       matrix:
         os: [ ubuntu-20.04, macos-11 ]
-        cxx: [ clang++, g++-9 ]
+        cxx: [ clang++, g++-10 ]
         build_type: [ Debug, Release ]
 
     steps:
     - name: which CXX
       run: |
         which ${{matrix.cxx}}
         ${{matrix.cxx}} --version
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: mkdir bin
       run: mkdir bin
     - name: cmake