Update telemetry settings to reflect the effect they have

The telemetry setting on the profile page is unclear about what it affects. It should clarify that opting in/out only affects personal data, and that business-/environment-level data is always collected.

Suggested text:
> * [ ] Opt in to personal data in Altis Telemetry
>
> *Altis collects business-level telemetry data about the performance and use of your site. Opting in to personal data helps us improve Altis and develop better tools for you.*

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*Original description:*

Steps to reproduce:
1. Visit your user profile editing screen at `wp-admin/profile.php`
2. Ensure the "Opt in to Altis Telemetry" checkbox is unchecked
3. Observe that a JavaScript file is still loaded from `https://cdn.segment.com/analytics.js/v1//analytics.min.js`
4. Observe that a request is still sent to `https://api.segment.io/v1/p` with a payload that includes an `anonymousId` parameter that appears to remain static between page loads

No cookies are set for either of these domains, but given the above it appears my usage of Altis is still being tracked by a third party despite my opting out.