Consider ShadowDom removing for some key elements

[ianovalena]

Is your feature request related to a problem? Please describe.
When it takes to external library integration or some a11y cases, ShadowDom can be a blocker
Recently, we had 2 cases:

1. aria-describedby for CatTooltip doesn't work, because of 2 reasons: 1) aria-describedby attribute is assigned to a component wrapper(e.g. cat-button), but not to the tabbable element itself(e.g. button) and 2) even if we manage to assign it to intractable element, browsers are not looking for id from aria-describedby attribute outside of ShadowDom.
   Perhaps we can remove make Tooltip and button not shadow?
2. Using CatButton as Swiper.js navigation buttons. Swiper allows using custom buttons for navigation and linking them by id, but when it comes to disabling (in case there is nothing to swipe), it tries to find the HTML button element to set disable="true" and can't find it in the ShadowDom. We need to create crazy workarounds to be able to keep disabling.

Describe the solution you'd like
Discuss one more time what the pros and cons of ShadowDom are, and do we really need it. If not, update some key components like Button to not use ShadowDom