Unnecessary focusable and tabindex in an OverflowMenu component

[kaushalnavneet]

focusable="false" in a span component and tabindex="0" in a button component

Found while using OverflowMenu component of carbon-components-react

• carbon-components-react

Detailed description

--> The issue got reported as part of the Accessibility Testing of IBM Cloud Pipeline pages. @carmacleod, in this comment, has pointed out that:

• focusable="false" in a span element does not look okay as span doesn't support the focusable attribute.
• Also, tabindex="0" is set by default for a button whereas buttons are focusable and in the tab order by default.

--> These issues DO NOT cause any harm when it comes to the functionality of the component but it doesn't look good.
--> I tried to get rid of these minor issues in the pipeline-ui code where OverflowMenu component is called. However, it looks like the default values are set at these places - for focusable and for tabindex.

--> Please consider taking care of these minor issues inside the carbon-component itself or it would be helpful to provide a feature to disable these attributes inside the components where it is not necessary or recommended.