fix: permission page footer bg (#38497)

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## **Description**

Remove footer background (alternate) that differs from body (default)
reported as a bug in
https://consensyssoftware.atlassian.net/browse/CEUX-770

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CHANGELOG entry: fix: permission page footer background

## **Related issues**

Fixes: https://consensyssoftware.atlassian.net/browse/CEUX-770

## **Manual testing steps**

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<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Removes the alternate background color from the permission page footer
container to match the body background.
> 
> - **UI (permissions)**:
> - In
`ui/components/app/permission-page-container/permission-page-container.component.js`,
remove `BackgroundColor.backgroundAlternative` from the footer `Box`,
leaving only `display` and `flexDirection`.
>   - Drop unused `BackgroundColor` import.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
afa62e2. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: n3ps

ui/components/app/permission-page-container/permission-page-container.component.js

@@ -14,7 +14,6 @@ import SnapPrivacyWarning from '../snaps/snap-privacy-warning';
 import { getDedupedSnaps } from '../../../helpers/utils/util';
 
 import {
-  BackgroundColor,
   Display,
   FlexDirection,
 } from '../../../helpers/constants/design-system';
@@ -231,11 +230,7 @@ export default class PermissionPageContainer extends Component {
           selectedAccounts={selectedAccounts}
           allAccountsSelected={allAccountsSelected}
         />
-        <Box
-          display={Display.Flex}
-          backgroundColor={BackgroundColor.backgroundAlternative}
-          flexDirection={FlexDirection.Column}
-        >
+        <Box display={Display.Flex} flexDirection={FlexDirection.Column}>
           {targetSubjectMetadata?.subjectType !== SubjectType.Snap && (
             <PermissionsConnectFooter />
           )}