Adds HTML title elements to templates that extend either `base.html`,
`portico.html` or `portico_signup.html`, and that are not website
portico landing pages that will use the `PAGE_TITLE` variable to set
the HTML title element (see following commit in series).
Also, updates some templates for missing translation tags.
As a general rule, we want the title element (and page content)
translated. Exceptions that are updated in this commit are templates
used in the development environment, analytics templates that are used
by staff and templates related to Zephyr.
This commit extends the template for "choose email" to mention for
users who have unverified emails that they need to verify them before
using them for Zulip authentication.
Also modified `social_auth_test_finish` to assert if all emails
are present in "choose email" screen as we need unverified emails
to be shown to user and verified emails to login/signup.
Fixes#12638 as this was the last task for that issue.
I added the `white-box` as it was in the other similar pages
(`/accounts/go`).
In order to be able to style it better, I removed the buttons and added
`div`s instead, then added click handler for submitting the form.
If the email is associated to a Zulip account, the avatar of the account
is displayed and the text `Log in`, otherwize a `+` sign is
displayed and the text `Create new account`.
I changed the class of the title in order to use the same styling as the
other similar pages (like `/accounts/go` or `/login`).
Changed the related test.
Previously, our Github authentication backend just used the user's
primary email address associated with GitHub, which was a reasonable
default, but quite annoying for users who have several email addresses
associated with their GitHub account.
We fix this, by adding a new screen where users can select which of
their (verified) GitHub email addresses to use for authentication.
This is implemented using the "partial" feature of the
python-social-auth pipeline system.
Each email is displayed as a button. Clicking on that button chooses
the email. The email value is stored in a hidden input above the
button. The `primary_email` is displayed on top followed by
`verified_non_primary_emails`. Backend name is also passed as
`backend` to the template, which in our case is GitHub.
Fixes#9876.