🔇 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/Nav/SettingsTabs/Speech/Speech.tsx

@@ -167,7 +167,7 @@ function Speech() {
             value="simple"
             style={{ userSelect: 'none' }}
           >
-            <Lightbulb />
+            <Lightbulb aria-hidden="true" />
             {localize('com_ui_simple')}
           </Tabs.Trigger>
           <Tabs.Trigger
@@ -180,7 +180,7 @@ function Speech() {
             value="advanced"
             style={{ userSelect: 'none' }}
           >
-            <Cog />
+            <Cog aria-hidden="true" />
             {localize('com_ui_advanced')}
           </Tabs.Trigger>
         </Tabs.List>