Table: adds the ability to change the table role

[tinkertrain]

Feature

We add a new table prop tableRole which changes the role attribute of the table element for special cases that require it.

When we change this attribute to something other than "table", we also make other attribute changes (in sortable tables)

• th no longer get the aria-sort attribute set
• Instead we add a aria-label attribute on the button inside the th, that reads "Sorted {columnName} name {order}" for example: "Sorted by name ascending"

We also adjust the row border focus from 2px to 3px
And we update all table tests to use testing-library

[knicklabs]

Looks good @tinkertrain! I'll go ahead and ship this as we discussed in Slack.