[FxA] Update Footer component

[punamdahiya]

Update Footer component as per new UI specs https://mozilla.github.io/testpilot-assets/Firefox_Screenshots/NEW_FxA_Integration/my-shots

[chenba]

Note that there's a small bug with the current footer. As a side effect of #4819 and the current auth check, the "Remove All Data" link is displayed to all Firefox users who visited more than one shot (or same shot more than once)--that is, has a user cookie--but have never created a shot.

I propose that we only show "Remove All Data" to the owner of the shot.

@johngruen ^ ?

[johngruen]

@chenba agree