Add Jetpack SSO connect flow

[brbrr]

adds SSO connect flow as requested in #777

To test this specific flow:

0. decrypt updated config. make sure subscriberUser is in your confg
1. Set JETPACKHOST env var to PRESSABLE / JN: e.g export JETPACKHOST=PRESSABLE
2. run the test: ./node_modules/.bin/mocha ./specs-jetpack-calypso/wp-jetpack-sso-connect-spec.js -g 'Connect via SSO'

[seear]

@brbrr I'm having trouble running this new spec locally. I'm set up using the all new instructions (great by the way!) and can run the jp connect spec ok using:
./node_modules/.bin/mocha specs-jetpack-calypso/wp-jetpack-connect-spec.js
and all those tests pass.

When I run:
./node_modules/.bin/mocha specs-jetpack-calypso/wp-jetpack-sso-connect-spec.js

I get:

1) Jetpack Connect: (desktop) Disconnect expired sites: @parallel @jetpack Can log in:
     Error: Account key 'jetpackUserWPCOM' not found in the configuration

[brbrr]

@seear Ah, sorry. I've added testing steps, so with defined JETPACKHOST - it should be fine.

[seear]

It's so great to have an e2e test for this flow, because it is one of the most fiddly to test manually and often gets missed out.

The tests pass for me. Code looks fine. Great work 👍

[seear]

Would be good to factor this removeSites function out so that it can be shared with the jetpack connect spec. That can be for a future PR because this one is large already.

[brbrr]

@Automattic/flowpatrol ready for review :)

[rachelmcr]

I noticed that this spec is set up to always use Jurassic Ninja as the host, even when JETPACKHOST is set to a different host (e.g. Pressable). What do you think of writing the spec in a way that it can be run on Jetpack sites on different hosts?

[brbrr]

Thanks for your suggestion @rachelmcr
I've updated the flow to re-use host specific site (with dataHelper.getJetpackSiteName()). To make it work - new WP.com account is created for every test. This spec did not clean up the list of subscribers (it may affect only PRESSABLE target)

[alisterscott]

Looks good and worked well for me:

 ./node_modules/.bin/mocha ./specs-jetpack-calypso/ -g 'Connect via SSO:'


  Jetpack Connect: (desktop)
    Connect via SSO: @parallel @jetpack
      ✓ Can register new Subscriber user (27810ms)
      ✓ Can log into WordPress.com (7130ms)
      ✓ Can log into site via Jetpack SSO (9686ms)
      ✓ Add new user as Subscriber in wp-admin (6209ms)
      ✓ Log out from WP Admin (4337ms)
      ✓ Can log in as Subscriber (6806ms)
      ✓ Can login via SSO into WP Admin (29769ms)


  7 passing (2m)

[alisterscott]