ci: update zig version regex in windows build

.github/workflows/test.yml

@@ -247,7 +247,7 @@ jobs:
         run: |
           # Get the zig version from build.zig so that it only needs to be updated
           $fileContent = Get-Content -Path "build.zig" -Raw
-          $pattern = 'const required_zig = "(.*?)";'
+          $pattern = 'buildpkg\.requireZig\("(.*?)"\)'
           $zigVersion = [regex]::Match($fileContent, $pattern).Groups[1].Value
           Write-Output $version
           $version = "zig-windows-x86_64-$zigVersion"