Fix issue - NewSiteCreationService can enter invalid state

[malinajirka]

Fixes #9138

This PR fixes a bug when NewSiteCreation service could enter an invalid state - the UI kept showing an infinite progress indicator.

This is happening when we start creating the site when we don't have an internet connection. The NewSiteCreationService.createSite(..) is not called since we check the internet availability before we call it. However, the service is created anyway when NewSiteCreationPreviewFragment binds to it in onResume. The default state of the service is IDLE, however this line prevents the service from actually starting the task when the user clicks on the retry button.

The flow works as expected when the internet connection is available since the NewSiteCreationService.createSite(..) is invoked before the service is created and therefore the state of the service is null and not IDLE.

To test:

• set "don't keep activities" in the developer settings

1. My Site
2. Switch Site
3. Plus sign icon
4. Create WordPress.com site
5. Select segment
6. Skip
7. Skip
8. Select a domain
9. Turn On Airplane mode
10. Create Site
11. Error is shown
12. Turn off Airplane mode
13. Retry
14. Press the home button
15. Go back to the app
16. Make sure the fullscreen error is not shown and the site is eventually created

Update release notes:

• [ x ] If there are user facing changes, I have added an item to RELEASE-NOTES.txt.

[oguzkocer]

Looks good Tested and works as expected!

I was actually going to ask about this in the original PR, but I wasn't sure if the IDLE step mattered or not. I should have asked it still, sorry for missing this!

[malinajirka]

@oguzkocer :D I would have told you it entered the IDLE state only in NewSiteCreationServiceManager.onStart() as I didn't realize the service is started when the fragment/activity binds to it. I'm sorry for the extra overhead testing this, I should have realized it and implement it correctly in the first place.