Update Transformer functionality to return value instead of string (#858)

src/WireMock.Net/Util/CultureInfoExtensions.cs

@@ -0,0 +1,40 @@
+using System;
+using System.Globalization;
+
+namespace WireMock.Util;
+
+internal static class CultureInfoUtils
+{
+    public static CultureInfo Parse(string? value)
+    {
+        if (value is null)
+        {
+            return CultureInfo.CurrentCulture;
+        }
+
+        try
+        {
+#if !NETSTANDARD1_3
+            if (int.TryParse(value, out var culture))
+            {
+                return new CultureInfo(culture);
+            }
+#endif
+            if (string.Equals(value, nameof(CultureInfo.CurrentCulture), StringComparison.OrdinalIgnoreCase))
+            {
+                return CultureInfo.CurrentCulture;
+            }
+
+            if (string.Equals(value, nameof(CultureInfo.InvariantCulture), StringComparison.OrdinalIgnoreCase))
+            {
+                return CultureInfo.InvariantCulture;
+            }
+
+            return new CultureInfo(value);
+        }
+        catch
+        {
+            return CultureInfo.CurrentCulture;
+        }
+    }
+}