fix(emails): Make Done button responsive after adding email

[karansapolia]

After adding new email in secondary email section, make
the done button responsive before email verification. Allow
done button to be clicked and panel to be closed. Do not
change the behavior of automatically opening panel if
secondary linked email is unverified.

fixes: #6242

@SorinaFlorean @lmorchard Request you to review please. Thank you.

[karansapolia]

For reference, the done button functions as expected now:

Current behavior allows users to click the 'done' button and close the panel. So users don't feel like the button is unresponsive. At the same time it retains the urgency of the callout to verify email by not changing the earlier behaviour of opening the secondary email panel automatically if the secondary email is unverified. Only that the user now has the option to close the panel if they so wish to.

[vbudhram]

@ryanfeeley A while back you made a bug to disable the Done button, ref #5897. This was caught by QA in https://github.com/mozilla/fxa-content-server/issues/6242, is this still considered a bug or should we close it?

[shane-tomlinson]

This repo has been deprecated and migrated to https://github.com/mozill/fxa. Please open this PR against that repo.