Remove unused command in Windows install step

Author: spoorcc

.github/workflows/build.yml

@@ -135,7 +135,6 @@ jobs:
     - name: Install binary
       if: matrix.platform == 'windows-latest'
       run: |
-        Get-ChildItem dfetch-package
         $file = "dfetch.msi"
         $log = "install.log"
         $procMain = Start-Process "msiexec" "/i `"$file`" /qn /l*! `"$log`"" -NoNewWindow -PassThru