Update Notifications.php

[marcelfolaron]

Link to ticket

#2442

Description

Mentioned Users were not notified because the user id was passed in as email address instead of the actual email address

Screenshot of the result

N/A

Checklist

• My code passes all test cases.
• My code passes our static analysis suite.
• My code passes our continuous integration process.

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should be exempt from the list.

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