Add UseDefinedRequestMatchers to ProxyAndRecordSettings (#821)

* .

* UseDefinedRequestMatchers

* ok

* .

* ClientIP

* t

* fix ut

* .

* cf

* cf2

src/WireMock.Net/Util/GuidUtils.cs

@@ -0,0 +1,16 @@
+using System;
+
+namespace WireMock.Util;
+
+internal interface IGuidUtils
+{
+    Guid NewGuid();
+}
+
+internal class GuidUtils : IGuidUtils
+{
+    public Guid NewGuid()
+    {
+        return Guid.NewGuid();
+    }
+}