floating-labels: remove `aria-label` in the `select` example

Created by: scottaohara

removes the aria-label on the floating label select example.

While it is understood that this is just an example, the visible text (label) of "Works with selects" and the aria-label="Floating label select example" created a WCAG 2.5.3 Label in name failure.

As the aria-label isn't necessary here since this select is already provided an accessible name by its label element, removing the unnecessary aria-label seems the best course of action as:

• removing it solves the WCAG issue
• it removes the potential implication to developers that they'd even need an aria-label here, let alone indirectly suggesting that it's ok for the visible text and accessible name to be out of alignment