feat: removed feature flag for confirmations screen (#27877)

This PR is to remove the feature flag from confirmations page

## **Related issues**

Fixes:
[https://github.com/MetaMask/MetaMask-planning/issues/3517](https://github.com/MetaMask/MetaMask-planning/issues/3517)

## **Manual testing steps**

1. Connect extension to a Dapp
2. Try to switch to a non enabled network from Dapp
3. In the confirmations screen, we should not see the network picker
4. The Definition list component should expand and popup should not show
up on click of See Details

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**
![Screenshot 2024-10-16 at 5 55
15 PM](https://github.com/user-attachments/assets/74984e47-2d42-4c10-9fa9-47193139edad)

### **After**
![Screenshot 2024-10-16 at 5 54
55 PM](https://github.com/user-attachments/assets/ee40e7fc-8980-4d17-9e0e-993cacb6d69c)


## **Pre-merge author checklist**

- [ ] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/develop/.github/guidelines/CODING_GUIDELINES.md).
- [ ] I've completed the PR template to the best of my ability
- [ ] I’ve included tests if applicable
- [ ] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [ ] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-extension/blob/develop/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [ ] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [ ] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.