bug: ion-tab-button isn't focusable when no href

[rbalet]

Prerequisites

• I have read the Contributing Guidelines.
• I agree to follow the Code of Conduct.
• I have searched for existing issues that already report this problem, without success.

Ionic Framework Version

v8.x

Current Behavior

ion-tab-button cannot be focused with the tab key when they do not have href

Expected Behavior

Being able to select them with tab

Steps to Reproduce

1. Use your tab until you select the search button.
2. You'll see you go direct to search without passing by other elements

Code Reproduction URL

https://stackblitz.com/edit/2uoossd8?file=index.html

Ionic Info

Ionic:

Ionic CLI : 5.4.16

Utility:

cordova-res : not installed
native-run : not installed

System:

NodeJS : v20.19.1
npm : 10.8.2
OS : Linux 5.0

Additional Information

I'd be glad to do a PR.
I would add the following

 @HostBinding('tabIndex')
  get tabIndex() {
    return 1
  }