[Bug]: sp-button with href fires twice

### Code of conduct

- [x] I agree to follow this project's code of conduct.

### Impacted component(s)

sp-button

### Expected behavior

When there is a valid href link, expect the sp-button click to only fire once.

### Actual behavior

The button fires twice - we noticed this in our analytics. Please see example: https://stackblitz.com/edit/vitejs-vite-ovhbrt2h?file=src%2Fmy-element.ts

### Screenshots

_No response_

### What browsers are you seeing the problem in?

Chrome

### How can we reproduce this issue?

1. Go to '...'
2. Click on '....'
3. Scroll to '....'
4. Check console
5. See error

### Sample code or abstract reproduction which illustrates the problem

_No response_

### Severity

None

### Logs taken while reproducing problem

_No response_

### Would you like to track this issue in Jira?

- [x] Yes, please tell me the ticket number!

Start with the sp-button component and the linked StackBlitz example, then reproduce the duplicate click in Chrome while inspecting the console or analytics event count. The issue names no repository file or test; done means a valid href produces exactly one click event, with the relevant regression coverage confirmed.

Written by the indexing model from the issue text.