Added aria-label to social share buttons for talkback (#491)
Added aria-label to social share buttons for talkback (#491)

* Added label to social share buttons for talkback

* Changed label wording to "share"

* to -> on

afilbert/ampstart,ampproject/ampstart,camelburrito/ampstart,ampproject/ampstart,afilbert/ampstart,camelburrito/ampstart,ampproject/ampstart