[BUG] Download files does not work from Exchange Admin Centre.

## To Reproduce
1. Browse to [portal.azure.com](https://portal.azure.com).
2. Connect to Cloud Shell (icon top right).
3. Upload a file to Cloud Shell (eg, sample.txt) - Manage Files | Upload file
4. Run the command `download sample.txt` (popup shows file with link and clicking the link downloads the file. This also works for Manage Files | Download file).
5. Browse [admin.exchange.microsoft.com](https://admin.exchange.microsoft.com/).
6. Run the command `download sample.txt` (popup shows file with link and clicking the link shows a new tab but file does not download).
7. Select Manage Files | Download file, type in sample.txt, click the Download button. Download File popup displays with link but clicking the link has the same result as step 6.
8. As a bonus try to click Manage files, Open File Share (nothing happens).

## Commands you ran
`download sample.txt`

## Observed Behavior
- All download options work in the Azure portal and Shell.
- All download options fail when using Cloud Shell in the Exchange Admin Centre.

Note: File upload works in both the Azure Portal and Exchange Admin Centre.

Include error output here
No error messages, all appears to work but the file download never initiates.

## Expected behavior
I expect the downloading files using the Cloud Shell to work in the same manner regardless of the portal being used.

## Is this specific to Cloud Shell?
Yes

## Interface information
https://admin.exchange.microsoft.com - Fail
https://shell.azure.com - Success
https://portal.azure.com - Success

まず、admin.exchange.microsoft.com で `download sample.txt` と Manage Files | Download file を再現し、その後、ダウンロードが機能する portal.azure.com と shell.azure.com と比較してください。Exchange Admin Centre で、ダウンロードと Manage Files | Open File Share アクションが、エラーやダウンロードされないタブなしに機能することを確認してください。

索引モデルが issue の本文から書いたものです。