Issue title: `Set brave as your default browser` modal popup is displayed with incorrect background color
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## Description 
<!--Provide a brief description of the issue-->
`Set brave as your default browser` modal popup is displayed with incorrect background-color

## Steps to Reproduce
<!--Please add a series of steps to reproduce the issue-->

   1. NA
  

## Actual result:
<!--Please add screenshots if needed-->

![image](https://user-images.githubusercontent.com/38657976/173283356-e383e58c-503a-47da-8f9a-cc888388abaa.png)

## Expected result:

![image](https://user-images.githubusercontent.com/38657976/173283406-1f0dc01d-8fa0-4ec2-be9f-b4ad4c91278a.png)

## Reproduces how often: 
<!--[Easily reproduced/Intermittent issue/No steps to reproduce]-->

Easy
## Brave version (brave://version info)
<!--For installed build, please copy Brave, Revision and OS from brave://version and paste here. If building from source please mention it along with brave://version details-->
<html>
<body>
<!--StartFragment-->

Brave | 1.41.58 Chromium: 103.0.5060.42 (Official Build) nightly (64-bit)
-- | --
Revision | de0d840bf9439c31bd86bf74f065c31fdf9b208d-refs/branch-heads/5060@{#667}
OS | Windows 10 Version 21H2 (Build 19044.1706)

<!--EndFragment-->
</body>
</html>

## Version/Channel Information:
<!--Does this issue happen on any other channels? Or is it specific to a certain channel?-->

- Can you reproduce this issue with the current release? No
- Can you reproduce this issue with the beta channel? No
- Can you reproduce this issue with the nightly channel? Yes

## Other Additional Information:

- Does the issue resolve itself when disabling Brave Shields? NA
- Does the issue resolve itself when disabling Brave Rewards? NA
- Is the issue reproducible on the latest version of Chrome? NA

## Miscellaneous Information:
<!--Any additional information, related issues, extra QA steps, configuration or data that might be necessary to reproduce the issue-->

cc: @brave/qa-team @rebron @mkarolin @emerick 
 Comments: 
 Comment 0: Looking now
 Comment 1: This is being uplifted as part of https://github.com/brave/brave-core/pull/13755 and can be verified using `1.40.101` or higher 👍 We should probably re-check to make sure that the above was actually fixed with `C103` now that we've merged it into `1.40.x`.
 Comment 2: ## Verified `PASSED` using 

Brave | 1.40.101 Chromium: 103.0.5060.42 (Official Build) (x86_64)
-- | --
Revision | de0d840bf9439c31bd86bf74f065c31fdf9b208d-refs/branch-heads/5060@{#667}
OS | macOS Version 11.6.7 (Build 20G630)

`Dark` | `Light`
-------|--------
<img width="1312" alt="Screen Shot 2022-06-16 at 12 01 45 PM" src="https://user-images.githubusercontent.com/387249/174146103-60377544-6d70-457d-a2c9-18fda7c37ac8.png"> | <img width="1282" alt="Screen Shot 2022-06-16 at 12 00 10 PM" src="https://user-images.githubusercontent.com/387249/174146136-241c2906-823c-411d-ab9d-d2f25b2fe52e.png">


 Comment 3: Verification **PASSED** on `PopOS 22.04 x64` using the following build(s):

```
Brave | 1.40.105 Chromium: 103.0.5060.53 (Official Build) (64-bit)
--- |---
Revision | a1711811edd74ff1cf2150f36ffa3b0dae40b17f-refs/branch-heads/5060@{#853}
OS | Linux
```

**`Example (Light Theme)`** | **`Example (Dark Theme)`**
--------------------------------|--------------------------------
![image](https://user-images.githubusercontent.com/2602313/174522348-74ba9d6b-d41f-4393-88bd-ef528260b34f.png) | ![image](https://user-images.githubusercontent.com/2602313/174522561-ab047f50-c371-4e2b-be35-1b1cc3f2f3a6.png)
{'source': 'GithubIssues', 'repo_name_with_owner': 'brave/brave-browser', 'issue_id': 1268910191, 'repo_stars': 15428.0}