Update CI to Ubuntu 20.04 and to newer versions of actions

.github/workflows/windows.yml

@@ -41,7 +41,7 @@ jobs:
             standard: 20
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
 
     - name: Create Build Environment
       run: cmake -E make_directory ${{runner.workspace}}/build
@@ -82,7 +82,7 @@ jobs:
         release: false
         msystem: ${{matrix.sys}}
         pacboy: cc:p cmake:p ninja:p lld:p
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - name: Configure
       run: cmake -B ../build -DBUILD_SHARED_LIBS=ON -DCMAKE_BUILD_TYPE=Debug
       env: { LDFLAGS: -fuse-ld=lld }