build: switch coverage-windows to windows-2022

GitHub has updated the `windows-2025` runner to Visual Studio 2026.
Since Node.js 22.x does not support compilation on VS2026, switch
the workflow to `windows-2022` which still has the earlier version
of Visual Studio.

Signed-off-by: Richard Lau <richard.lau@ibm.com>

Author: richardlau

.github/workflows/coverage-windows.yml

@@ -43,7 +43,7 @@ permissions:
 jobs:
   coverage-windows:
     if: github.event.pull_request.draft == false
-    runs-on: windows-2025
+    runs-on: windows-2022
     steps:
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8  # v5.0.0
         with: