.Net Remove SKCancelEventArgs unneeded finalizer (#3249)

### Motivation and Context

Garba Collection will handle this scenario normally

### Description

Removal of unneeded implementation.

### Contribution Checklist

- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

dotnet/src/SemanticKernel.Abstractions/Events/SKCancelEventArgs.cs

@@ -29,12 +29,4 @@ public void Cancel()
     {
         this._cancelTokenSource.Cancel();
     }
-
-    /// <summary>
-    /// Dispose resources.
-    /// </summary>
-    ~SKCancelEventArgs()
-    {
-        this._cancelTokenSource.Dispose();
-    }
 }