fix: adjust spacing of quote rate in swaps (#28051)

## **Description**

Cherry-pick of #28016
into v12.6

[![Open in GitHub
Codespaces](https://github.com/codespaces/badge.svg)](https://codespaces.new/MetaMask/metamask-extension/pull/28016?quickstart=1)

## **Manual testing steps**

1. Start a swap
2. Notice that the quote rate is back on one line and the value is
left-aligned

## **Screenshots/Recordings**

### **Before**

![Screenshot 2024-10-11 at 11 32
09 AM](https://github.com/user-attachments/assets/aae5da2f-ae66-46f5-9168-6c6ed496a2a8)


### **After**

<img width="359" alt="Screenshot 2024-10-22 at 12 13 50 PM"
src="https://github.com/user-attachments/assets/f5974e8a-62a6-464e-a037-b7ce38774f42">


## **Pre-merge author checklist**

- [X] 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).
- [X] I've completed the PR template to the best of my ability
- [X] I’ve included tests if applicable
- [X] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [X] 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.

ui/pages/swaps/prepare-swap-page/index.scss

@@ -263,7 +263,7 @@
   }
 
   &__exchange-rate-display {
-    color: var(--color-text-alternative);
+    width: auto !important;
   }
 }