ci: Install zstd in Windows build container

Author: mborgerson

.github/workflows/build-windows.yml

@@ -32,6 +32,9 @@ jobs:
       uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v4
       with:
         name: src
+    - name: Install zstd
+      if: ${{ matrix.arch == 'arm64' }}
+      run: apt-get install zstd
     - name: Extract source package
       run: tar -xf xemu-${{ inputs.pkg_version }}.tar.zst --strip-components=2
     - name: Initialize compiler cache