Bulk optimization progress bar/icon gets hidden although it isnot finished yet

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• Made sure you’re on the latest version => 2.1.2
• Used the search feature to ensure that the bug hasn’t been reported before

Describe the bug
The progress bar and loading icon at bulk optimization after Imagify all, gets hidden after some time although optimization is not done yet

To Reproduce
Steps to reproduce the behavior:

1. Install and activate Imagify on a website with some unoptimized images
2. In the settings page add the theme folder to be optimized
3. On the bulk optimization tab, click Imagify all
4. notice the progress bar and loading icon beside the media library and custom folder

Expected behavior
The progress bar is displayed till finishing optimization as long as the quota is there

Screenshots
If applicable, add screenshots to help explain your problem.
screen-capture (67).webm

Additional context
Add any other context about the problem here.

• To avoid confusion about quota, test with infinite account
• If we reoptimize any image at the media library or custom folder, it will keep loading till n time and probably won't work till bulk optimization is done

Acceptance Criteria (for WP Media team use only)
Clear instructions for developers, to be added before the grooming

Reproduce the issue from the bulk optimization tab after adding a theme folder and clicking Imagify all, using an account with an infinite quota. Check why the progress bar and loading icon disappear before optimization finishes; done means they remain visible until the bulk optimization completes and later individual optimization works.