✨ Remove possibility of setting `PoolCandidate` status directly

[tristan-orourke]

✨ Feature

PoolCandidates should move through states in a guided way, like a state machine (see #9149). Now that we have the UI for doing so, we should remove the controls that let admins choose and update PoolCandidate.status directly.

🕵️ Details

Remove any UI that allows users to select PoolCandidate.status from a dropdown and save it. Delete updatePoolCandidateStatus and any references to it. (Where it was used to update expiry date, we should be able to use qualifyCandidate instead.)

🎨 Design File

I know this needs to be removed from the candidate page. Its possible these controls appear elsewhere as well.

🧑‍🎨 Designer

@Jerryescandon

📸 Screenshot

Note: the figma design does not include the form to directly set status, as it was always meant to be temporary.

🙋‍♀️ Proposed Implementation

(optional) Do you have a proposed implementation?

✅ Acceptance Criteria

A set of assumptions which, when tested, verify that the feature was properly implemented.

• [ ] updatePoolCandidateStatus mutation is deleted
• [ ] Users cannot set PoolCandidate.status directly (profile and candidate pages)

🛑 Blockers

Issues which must be completed before this one.

### Blocked By
- [ ] #9198 
- [ ] #9197 
- [ ] #9140

[github-actions[bot]]

Status: Ready to merge :heavy_check_mark:

Issues blocking this PR:

• 9198 :heavy_check_mark:

• 9197 :heavy_check_mark:

• 9140 :heavy_check_mark:

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  This comment was automatically written by the Blocking Issues bot, and this PR will be monitored for further progress.

[brindasasi]

We want to wait on this feature. We will come back if this is required to implement