Temporarily disable Windows CI builds

It's better to disable them that to get in the habit of ignoring the CI fails
from the following two issues; this can be reverted once either is fixed.

glib has a bug where it builds things out of order which results in it failing
to build the dependencies, which fails the build.
microsoft/vcpkg#26601

vcpkg also has a bug where it very often fails to use the cache of the
previously built dependencies even if none of them changed, which then makes it
rebuild all the dependencies again.
microsoft/vcpkg#28722

If the glib bug was fixed, then the errors wouldn't happen since rebuilding the dependencies wouldn't fail.
If the caching bug was fixed, then the errors wouldn't happen since it'd just reuse the cached dependencies.

.github/workflows/ci-main.yml

@@ -243,71 +243,6 @@ jobs:
       - name: Run unit tests
         run: ./run_boost_tests --path=projectfiles/Xcode/build/"$CFG" --executable=unit_tests
 
-  windows:
-    strategy:
-      fail-fast: false
-      matrix:
-        cfg: [Debug, Release]
-    env:
-      CFG: ${{ matrix.cfg }}
-    defaults:
-      run:
-        shell: cmd
-    runs-on: windows-2019
-
-    steps:
-      - uses: actions/checkout@v3
-        with:
-          submodules: "recursive"
-
-      - name: Cache object files
-        id: windows-cache
-        uses: actions/cache@v3
-        with:
-          path: |
-            D:/a/wesnoth/vcpkg
-            D:/a/wesnoth/wesnoth/vcpkg_installed
-          key: win-cache-master-${{ matrix.cfg }}-0012
-
-      - name: Add msbuild to PATH
-        uses: microsoft/[email protected]
-
-      - name: Build vcpkg
-        run: |
-          git clone https://github.com/microsoft/vcpkg.git D:/a/wesnoth/vcpkg
-          cd D:/a/wesnoth/vcpkg
-          D:/a/wesnoth/vcpkg/bootstrap-vcpkg.bat
-
-      - name: Setup cmake
-        uses: jwlawson/[email protected]
-        with:
-          cmake-version: '3.20.6'
-
-      - name: Run cmake
-        run: |
-          cmake -DCMAKE_BUILD_TYPE=%CFG% -DENABLE_GAME=true -DENABLE_SERVER=true -DENABLE_CAMPAIGN_SERVER=true -DENABLE_TESTS=true -DENABLE_MYSQL=false -DENABLE_NLS=false -DVCPKG_TARGET_TRIPLET=x64-windows -DCMAKE_TOOLCHAIN_FILE=D:/a/wesnoth/vcpkg/scripts/buildsystems/vcpkg.cmake -DCMAKE_GENERATOR_PLATFORM=x64 -G "Visual Studio 16 2019" .
-
-# Trying to find the cause of the intermittent build failures. This assumes that the failure was during building glib,
-# but that seems regular enough that I'll check manually to see if it was.
-      - name: Store glib build log
-        uses: actions/upload-artifact@v3
-        if: failure()
-        with:
-          name: glib-log
-          path: D:/a/wesnoth/vcpkg/buildtrees/glib/package-x64-windows-*-out.log
-
-# delete buildtrees directory to free up space after cmake invokes vcpkg to build the dependencies
-# otherwise the job was failing when trying to write a .obj file
-# building vcpkg on the more spacious C drive didn't work since for some reason vcpkg decides to not create the pango/cairo pkgconfig files there
-      - name: Build wesnoth, wesnothd, campaignd and unit tests
-        run: |
-          rmdir /s /q D:\a\wesnoth\vcpkg\buildtrees
-          MSBuild.exe wesnoth.sln -p:Configuration=%CFG%
-
-      - name: Run WML unit tests
-        if: matrix.cfg == 'Release'
-        run: python run_wml_tests -v -g -c -t 20 -p D:/a/wesnoth/wesnoth/%CFG%/wesnoth.exe
-
 # run after all other jobs have completed to check overall build status
   discord-notification:
     runs-on: ubuntu-20.04