add Blog token health check

[leogermani]

Adapts the local suite tests to work with user-less.

If the test is called in a context without a logged in user and without a connection owner, it will skip the check for the user token health.

If there is a connected logged in user, or if the site has a connected owner, it will also check for the user token health

Changes proposed in this Pull Request:

• Adapt local test suite for user-less connections

Jetpack product discussion

Does this pull request change what data or activity we track or use?

N/A

Testing instructions:

• Connect your site only at a site level (if not using the docker env, you need to activate user-less testing mode)
• Visit the Jetpack Debugger no WP Admin
• Visit the Jetpack Debugger on jptools.wordpress.com .
• Make sure tests pass
• Connect the user and run the tests again

Invalidate the Blog token and see that the test fails

[test-case-reminder]

Here are some suggested test cases for this PR.

Connection

• In-place connection with free plan
• In-place connection with paid plan
• In-place connection with product purchase
• Classic connection. Use Safari, or set a constant JETPACK_SHOULD_NOT_USE_CONNECTION_IFRAME to true
• Disconnect/reconnect connection
• Secondary user connection
• Connection on multisite

Verify that the changes are compatible with the plugins that use the connection package.

• WooCommerce Payments
• Jetpack Boost
• Previous versions of Jetpack

If you think that suggestions should be improved please edit the configuration file here. You can also modify/add test-suites to be used in the configuration file.

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

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Jetpack plugin:

• Next scheduled release: April 6, 2021.
• Scheduled code freeze: March 29, 2021.

[fgiannar]

Hi Leo!

Thanks for working on this!
I left some thoughts/suggestions inline.

[fgiannar]

Two suggestions :)

1. How about we use $m->is_userless() here?
2. I was thinking if it would be more straightforward to keep all token health checks in the same test? This way we don't need to skip it in case of a user-less connection or run a duplicate test in case of a full connection.

[fgiannar]

LGTM 🥇