[Bug]: Tabs can still be focused after setting disabled attribute

### Code of conduct

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

### Impacted component(s)

sp-tabs

### Expected behavior

Tabs should not be focusable when disabled.

### Actual behavior

Tabs are focusable after setting the disabled property on the sp-tabs DOM element.

### Screenshots

_No response_

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

Chrome

### How can we reproduce this issue?

1. Go to https://studio.webcomponents.dev/edit/LOFTH0ZjO3EfPsuQ7PlA/src/index.ts?p=stories
2. Add the "disabled" attribute on sp-tabs in the Elements panel of dev tools
3. Notice how the "focusable" attribute remains and you can navigate the tabs by tabbing and using the arrow keys

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

_No response_

### Severity

SEV 3

### Logs taken while reproducing problem

_No response_

Start with the sp-tabs component and reproduce the issue using the linked webcomponents.dev example in Chrome. Inspect how setting the disabled attribute affects the focusable attribute and keyboard navigation; done means disabled tabs are no longer focusable or navigable by keyboard.

Written by the indexing model from the issue text.