ci: remove msys attempt

Seems we need an expert!

.github/workflows/build-and-test.yml

@@ -14,7 +14,6 @@ jobs:
         os:
           - ubuntu-latest
           - macos-latest
-          - windows-latest
 
     steps:
       - uses: actions/checkout@v2
@@ -30,15 +29,6 @@ jobs:
         run: |
           brew install meson ninja libgpg-error libtool pkg-config glib gmime xapian
 
-      - if: contains(matrix.os, 'windows')
-        uses: msys2/setup-msys2@v2
-        with:
-          msystem: MINGW64
-          update: true
-        name: windows-deps
-        run: |
-          pacman -S base-devel msys-devel gcc git meson mingw-w64-gmime mingw-w64-xapian-core
-
       - name: configure
         run: ./autogen.sh -Dguile=disabled