fix: replace disabled attribute with CSS class for Bootstrap 5 compatibility

[anishsarangi]

…ibility

[vbanos]

@anishsarangi the attribute disabled is a standard HTML attribute.
What does it have to do with bootstrap compatibility?

If you want to style disabled buttons, you can use the :disabled CSS selector to do it.
https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors/:disabled