A11Y-Improvements for FIP Validator

[therobrob]

Regarding #684 there are three a11y-issues i want to address:

Issue 1) are there any improvements for the table-implementation? We could add an caption to give context for screenreader users. More ideas are written down here: https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Table_accessibility

Issue 2) Some buttons on the operator pages are disabled (mostly the FIP Global price ones): Should these only be used as div elements, because they won’t get an interactive status? We also should remove the aria-label, because they aren’t active

Issue 2,5) The interactive buttons don’t reveal the status information to screenreader users for now. They only get the information about the action interacting with them.

Issue 3) the information in the cards should be connected with each others semantically