Use proper aria label

[ewmcelvaney]

We can't create our own aria labels, instead we need to use ones that are values that are specified in aria's spec.

The section with the map has an aria-label that would be better suited as alt text. There should be a new aria label put in once the current aria label has been converted to alt text; this should be typed as aria-label="graphics-legend".

This is the area where the issue was found: