Hash-check windows CI dependencies

.github/workflows/build.yml

@@ -157,8 +157,7 @@ jobs:
       - name: Install compiler
         run: |
           sudo apt-get update && sudo apt-get install cmake -qyy
-          wget http://minetest.kitsunemimi.pw/mingw-w64-${{matrix.config.arch}}_11.2.0_ubuntu20.04.tar.xz -O mingw.tar.xz
-          sudo tar -xaf mingw.tar.xz -C /usr
+          ./scripts/ci-get-mingw.sh ${{matrix.config.arch}}
 
       - name: Build
         run: |