Updated the BrowserStack version of Chrome used for the acceptance tests

Author: jan-molak

build-monitor-acceptance/src/test/resources/serenity.conf

@@ -1,9 +1,9 @@
 browserstack {
   url             = ""          // set by maven, so that the remote browser is only used on Jenkins
-  browser_version = "48.0"
+  browser_version = "57.0"
   browser         = "chrome"
   os              = "Windows"
-  os_version      = "7"
+  os_version      = "10"
 
   debug = true
   local = true