Switch to downloading prebuilt release artifacts instead of a submodule

.github/workflows/build-win-mac.yml

@@ -34,6 +34,10 @@ jobs:
           submodules: 'recursive'
           fetch-depth: 1
 
+      - name: Download dependencies (Windows)
+        if: runner.os == 'Windows'
+        run: powershell ./setup-deps.ps1
+
       - name: Install create-dmg (macOS)
         if: runner.os == 'macOS'
         run: |