fixup path in build.yml

Author: spoorcc

.github/workflows/build.yml

@@ -135,7 +135,7 @@ jobs:
         msiexec /i "dfetch-package\\dfetch.msi" /qn /norestart
         $env:PATH
         Get-ChildItem $env:ProgramFiles
-        Get-ChildItem $env:"ProgramFiles(x86)"
+        Get-ChildItem ${env:ProgramFiles(x86)}
 
       shell: pwsh