Review copy of Cloud Connector status probes messages

Follow-up

The following discussion from !159579 (merged) should be addressed:

• @aregnery started a discussion: (+1 comment)

  @mkaeppler can we get @fneill to do a Technical Writing review? I realize this is just the first change, but I think she can really help us refine the return messages.

Example

Probes

License probe

This probe checks whether the customer has the right kind of license installed.

	success	failure (no license)	failure (wrong license)
current	Online Cloud License found	No license found	No Online Cloud license found
proposed	Subscription can be synchronized.	Subscription for this instance cannot be synchronized. Contact GitLab customer support to obtain a license.	Subscription for this instance cannot be synchronized. Contact GitLab customer support to upgrade your license.

Host probe

This probe checks whether the given network endpoint is reachable from the customer's GitLab instance.

	success	failure (host is unreachable)
current	#{host} reachable	#{host} unreachable
proposed	#{host} reachable.	#{host} could not be reached. If you use firewalls or proxy servers, make sure they allow traffic to this host.

Access probe

This probe checks whether all required Cloud Connector access data have been synchronized correctly from the Customers Portal.

	success	failure (data missing)	failure (data stale)	failure (token missing)	failure (token expired)
current	Access data is valid	Access data is missing	Access data is stale	Access token is missing	Access token has expired
proposed	Subscription synchronized successfully.	Subscription has not been synchronized before. Synchronize it manually as described here.	Subscription has not been synchronized recently. Synchronize it manually as described here.	Access credentials not found. Synchronize them manually as described here.	Access credentials expired. Synchronize them manually as described here.

End-to-end probe

This probe checks whether a real code completions request it sent was successful or not.

	success	failure (host is unreachable)
current	Code completion test was successful	Code completion test failed: #{error}
proposed	Handshake with GitLab Cloud services succeeded.	Handshake with GitLab Cloud services failed.