Need to build Cbc in order to get sdist

Author: tkralphs

.github/workflows/cibuildwheel.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-20.04, windows-2019, macos-10.15]
+        os: [ubuntu-20.04, macos-10.15]
 
     steps:
       - uses: actions/checkout@v2
@@ -35,6 +35,16 @@ jobs:
     steps:
       - uses: actions/checkout@v2
 
+      - name: Checkout coinbrew
+        uses: actions/checkout@v2
+        with:
+          repository: coin-or/coinbrew
+          path: coinbrew
+      - name: Build Cbc
+        run: |
+          bash coinbrew/coinbrew build [email protected] -j 16
+          export COIN_INSTALL_DIR=dist
+          
       - name: Build sdist
         run: pipx run build --sdist