Related to #250 - Timeout for regex

This prevents DoS via runaway regex evaluation.
100ms is more than generous for stripping non-alpahnumeric
characters from a date.

Author: craigfowler

CSF.Screenplay.Selenium/Tasks/EnterTheDate.cs

@@ -32,7 +32,9 @@ namespace CSF.Screenplay.Selenium.Actions
     public class EnterTheDate : IPerformable, ICanReport
     {
         const string nonNumericPattern = @"\D";
-        static readonly Regex nonNumeric = new Regex(nonNumericPattern, RegexOptions.Compiled | RegexOptions.IgnoreCase | RegexOptions.CultureInvariant);
+        static readonly Regex nonNumeric = new Regex(nonNumericPattern,
+                                                     RegexOptions.Compiled | RegexOptions.IgnoreCase | RegexOptions.CultureInvariant,
+                                                     TimeSpan.FromMilliseconds(100));
 
         readonly DateTime? date;
         readonly ITarget target;