Revise wording on the the Analytics initial setup screen (step 4) for secondary administrators

## Bug Description

If Analytics is setup already, any secondary admins will see the below, suggesting they should set it up (which isn't the case, as Analytics is already successfully setup).


Improve this by modifying the message shown to secondary administrators. An example could be the below:

~~To understand how visitors find and use your site, have Site Kit add [Painful Opinion _ new title](https://painfulopinion.s1-tastewp.com/) to Google Analytics for you.~~

To understand how visitors find and use your site, Site Kit can display Analytics data for [Painful Opinion _ new title](https://painfulopinion.s1-tastewp.com/) within the plugin dashboards. Ensure you have been granted access to this Analytics property.

An alternative is to not display the Analytics setup step, similar to how we don't display the Analytics setup option/checkbox during initial setup for the primary administrator who is setting up Site Kit.

## Screenshots

Below: _The Search Console setup step mentions that Search Console is already connected, as it should_


Below: _The Analytics setup step indicates that Site Kit will add their site to Analytics, when this isn't the case if the module is already connected._


The above suggestion is one suggestion based on some support testing for secondary administrators setting up the plugin. More [insights here](https://app.asana.com/0/1185360131189553/1204563795499396/f).

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## Acceptance criteria

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## Implementation Brief

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### Test Coverage

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## QA Brief

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## Changelog entry

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Start by locating the Analytics initial setup screen's step 4 and the message shown to secondary administrators, then compare it with the Search Console setup wording described in the issue. Done means the Analytics step no longer suggests that a secondary administrator will set up an already-connected module, with the selected wording covered by the relevant UI test.

Written by the indexing model from the issue text.