Downgrade to Windows Server 2022

* As reported by HDFGroup/hdf5#5885
* Caused by actions/runner-images#12677

Author: tbeu

.github/workflows/checkCI.yml

@@ -35,7 +35,7 @@ jobs:
             os: windows-latest
             compiler: msvc
           - toolchain: windows-mingw
-            os: windows-latest
+            os: windows-2022
             compiler: mingw
     steps:
       - name: Checkout code