Runner status cannot be "paused" [RUN-AS-IF-FOSS]

What does this MR do and why?

This change removes a data duplication in the GraphQL API by removing the PAUSED status as a possible result of the Ci::Runner status

The same change is announced for the REST API for "status", and "paused" will be removed in the next major release.

In both cases, when checking if a runner is "paused", API users are advised to check the boolean attribute "active" to be false instead.

Note: This MR deprecates paused in out REST API: #344648 (closed)

Screenshots or screen recordings

Our API will let us know if a runner is offline or online, even if paused 👍

How to set up and validate locally

There are 2 subtle API changes:

• GraphQL API: Paused runners' status will only be: online, offline, not_connected. paused will not appear.
• REST API: Paused runners' status will not be changed, but the paused result is deprecated.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #343262 (closed)