[build] fix chmod value for geenrated dotnet files

Author: titusfortner

Rakefile

@@ -784,9 +784,9 @@ namespace :dotnet do
     FileUtils.rm_f('build/dist/*dotnet*')
 
     FileUtils.copy('bazel-bin/dotnet/release.zip', "build/dist/selenium-dotnet-#{dotnet_version}.zip")
-    FileUtils.chmod(666, "build/dist/selenium-dotnet-#{dotnet_version}.zip")
+    FileUtils.chmod(0666, "build/dist/selenium-dotnet-#{dotnet_version}.zip")
     FileUtils.copy('bazel-bin/dotnet/strongnamed.zip', "build/dist/selenium-dotnet-strongnamed-#{dotnet_version}.zip")
-    FileUtils.chmod(666, "build/dist/selenium-dotnet-strongnamed-#{dotnet_version}.zip")
+    FileUtils.chmod(0666, "build/dist/selenium-dotnet-strongnamed-#{dotnet_version}.zip")
   end
 
   desc 'Upload nupkg files to Nuget'