🛠 Resolve RCS1277 violation

X10D/src/StringExtensions.cs

@@ -204,11 +204,16 @@
                 throw new ArgumentNullException(nameof(str));
             }
 
+            return SplitInternal();
+
+            IEnumerable<string> SplitInternal()
+            {
                 for (var i = 0; i < str.Length; i += chunkSize)
                 {
                     yield return str.Substring(i, Math.Min(chunkSize, str.Length - i));
                 }
             }
+        }
 
         /// <summary>
         /// Converts a <see cref="string"/> to a <see cref="SecureString"/>.