Toolbar icon for Commerce inbox

Icon added, sprite generated and styles updated.

Results:

@majmunbog MR#2 has been successfully applied, the issue is resolved, and the bell icon is showing well.

Attaching Scrrenshot.

@majmunbog

Praise: For creating the icon in the same way as the others so it works flawlessly in darkmode 👏

Let's move forward with this 👏

Thanks!

Automatically closed - issue fixed for 2 weeks with no activity.