chore: fix typo in CallbackExtensions.cs (#4301)

specificy -> specificity



---

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[Apache 2.0 license]: https://www.apache.org/licenses/LICENSE-2.0

packages/@jsii/dotnet-runtime/src/Amazon.JSII.Runtime/CallbackExtensions.cs

@@ -65,7 +65,7 @@ out object? result
                 return null;
             }
 
-            throw new ArgumentException("Callback does not specificy a method, getter, or setter to invoke");
+            throw new ArgumentException("Callback does not specify a method, getter, or setter to invoke");
         }
 
         private static CallbackResult? InvokeMethod(InvokeRequest request, IReferenceMap referenceMap)
@@ -251,4 +251,4 @@ private CallbackResult(TypeReference type, bool isOptional, object? value) : bas
 
         public object? Value { get; }
     }
-}
+}