[BUG] PWA - duplicate notifications

[SnirShechter]

Describe the bug
When installing the application after allowing notifications, the notifications are sent twice: once via the PWA and once via Chrome.

To Reproduce
Steps to reproduce the behavior:

1. Start a training
2. Go to the training page and allow notifications
3. Install the application as a PWA
4. End the training

Two notifications will be sent.
Expected behavior
There should only be one notification - the PWA's.

Possible solutions
We should check of a way to disable notifications and do it upon installing the application and/or add a button for users.