We are now using the `session-data` method of the Beacon API to send
site information to HelpScout
(https://developer.helpscout.com/beacon-2/web/javascript-api/#beacon-session-data).
This method has a limit of 20 attribute-value pairs and since we had
more, it was necessary to combinte a few values under the same
attribute.
[MAILPOET-4525]
We were calling the wrong Beacon API method to send system info
data to HelpScout when users create tickets inside WordPress. This
commit fixes this by calling the method `session-data` instead of
`identify`. It is likely that `identify` was the correct method in the
past, but the Beacon API changed
(https://developer.helpscout.com/beacon-2/web/javascript-api/).
Nowadays, the `identify` method is used to add data to the HelpScout
users and fields need to be created in advance in the HelpScout web
interface. `session-data` is used to add information to the ticket which
is what we are trying to achieve. Only `name` and `email` should still
be passed to `identify` to make it possible to match the correct
HelpScout user.
[MAILPOET-4525]
This commit adds a new flag to \MailPoet\Helpscout\Beacon::getData() to
mask half of the API key when this method is used to get information for
the System Info page. When it is used to pass information to HelpScout
nothing should change and the full key will be returned.
[MAILPOET-4009]
