fix: content dialog styling is being applied to all dialogs (#28739)

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## **Description**
Problem: A scss change for preventing modal scrolling in the bridge
experience was added and got unintentionally applied to all modals.

Solution: Nest the styling within the `quotes-modal` className
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## **Related issues**

Fixes: #28722

## **Manual testing steps**

1. Visually inspect Swap token picker
2. Visually inspect tx "Speed up" and "Cancel" layout

## **Screenshots/Recordings**

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before and after of your change. -->

### **Before**
See bug report screenshots

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### **After**
![Screenshot 2024-11-26 at 9 48
13 AM](https://github.com/user-attachments/assets/f5bd07d5-f062-4489-8c11-5e64f88eed75)


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ui/pages/bridge/quotes/index.scss

@@ -63,7 +63,9 @@
   }
 }
 
-.mm-modal-content__dialog {
-  display: flex;
-  height: 100%;
+.quotes-modal {
+  .mm-modal-content__dialog {
+    display: flex;
+    height: 100%;
+  }
 }