chore: Fix boolean setting for ENABLE_CONFIRMATION_REDESIGN on `con…

…fig.yml` (#25485)

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## **Description**

On [this
PR](https://github.com/MetaMask/metamask-extension/pull/25258/files) we
moved away from representing a boolean with `1` or `0`.

However, simply using `true` throws linting errors (see image and thread
linked below).

This PR explicitly sets the variable as a string to eliminate said
errors.


![image](https://github.com/MetaMask/metamask-extension/assets/13814744/d2e83e05-a55e-4e91-8271-b82fd455ace9)
([source
thread](https://consensys.slack.com/archives/CTQAGKY5V/p1718307835430529))


[![Open in GitHub
Codespaces](https://github.com/codespaces/badge.svg)](https://codespaces.new/MetaMask/metamask-extension/pull/25485?quickstart=1)

## **Related issues**

Fixes: N/A

## **Manual testing steps**

1. Go to this page...
2.
3.

## **Screenshots/Recordings**

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

### **Before**

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### **After**

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## **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.

.circleci/config.yml

@@ -859,7 +859,7 @@ jobs:
           at: .
       - run:
           name: Build extension for testing
-          command: ENABLE_CONFIRMATION_REDESIGN=true yarn build:test
+          command: ENABLE_CONFIRMATION_REDESIGN="true" yarn build:test
       - run:
           name: Move test build to 'dist-test' to avoid conflict with production build
           command: mv ./dist ./dist-test-confirmations
@@ -881,7 +881,7 @@ jobs:
           at: .
       - run:
           name: Build extension for testing
-          command: ENABLE_CONFIRMATION_REDESIGN=true yarn build:test:mv2
+          command: ENABLE_CONFIRMATION_REDESIGN="true" yarn build:test:mv2
       - run:
           name: Move test build to 'dist-test-confirmations-mv2' to avoid conflict with production build
           command: mv ./dist ./dist-test-confirmations-mv2
@@ -1086,7 +1086,7 @@ jobs:
             fi
           no_output_timeout: 5m
           environment:
-            ENABLE_CONFIRMATION_REDESIGN: true
+            ENABLE_CONFIRMATION_REDESIGN: "true"
       - store_artifacts:
           path: test-artifacts
           destination: test-artifacts
@@ -1377,7 +1377,7 @@ jobs:
             fi
           no_output_timeout: 5m
           environment:
-            ENABLE_CONFIRMATION_REDESIGN: true
+            ENABLE_CONFIRMATION_REDESIGN: "true"
       - store_artifacts:
           path: test-artifacts
           destination: test-artifacts