🔇 fix: Hide Button Icons from Screen Readers (#10776)

If you've got a screen reader that is reading out the whole page,
each icon button (i.e., `<button><SVG></button>`) will have both
the button's aria-label read out as well as the title from the
SVG (which is usually just "image").

Since we are pretty good about setting aria-labels, we should instead
use `aria-hidden="true"` on these images, since they are not useful
to be read out.

I don't consider this a comprehensive review of all icons in the app,
but I knocked out all the low hanging fruit in this commit.

client/src/components/Chat/Input/CollapseChat.tsx

@@ -41,9 +41,9 @@ const CollapseChat = ({
             )}
           >
             {isCollapsed ? (
-              <ChevronUp className="h-full w-full" />
+              <ChevronUp className="h-full w-full" aria-hidden="true" />
             ) : (
-              <ChevronDown className="h-full w-full" />
+              <ChevronDown className="h-full w-full" aria-hidden="true" />
             )}
           </button>
         }