Improve speed for windows Get-CimInstance

This only fetches a single property which is faster

lib/concurrent-ruby/concurrent/utility/processor_counter.rb

@@ -69,7 +69,7 @@ def compute_physical_processor_count
                 cores.count
               when /mswin|mingw/
                 # Get-CimInstance introduced in PowerShell 3 or earlier: https://learn.microsoft.com/en-us/previous-versions/powershell/module/cimcmdlets/get-ciminstance?view=powershell-3.0
-                result = run('powershell -command "Get-CimInstance -ClassName Win32_Processor  | Select-Object -Property NumberOfCores"')
+                result = run('powershell -command "Get-CimInstance -ClassName Win32_Processor -Property NumberOfCores | Select-Object -Property NumberOfCores"')
                 if !result || $?.exitstatus != 0
                   # fallback to deprecated wmic for older systems
                   result = run("wmic cpu get NumberOfCores")