fix windows CI => project file integration broken on windows-latest

* use windows-2019 until updated project files are usable on 2022

Signed-off-by: Stephen L Arnold <nerdboy@gentoo.org>

.github/workflows/build-windows.yml

@@ -4,7 +4,7 @@ jobs:
 
   build-windows:
 
-    runs-on: windows-latest
+    runs-on: windows-2019
 
     steps: