Describe the bug

When a user (regular or admin) is blocked, the expected result is that the user will not receive notifications about activity on the site for many reasons (avoiding spam, limiting access to content to members only, etc.). Now as an admin site you haven't any way to avoid this.

To Reproduce

Previous conditions for "User X"

• User X has all notifications activated in realtime
• User X follows the activity of the participation space “A”

Steps to follow as a site administrator:

1. Publish a content in space "A" and check if user X receive the notification. (He received. OK)
2. Block User X
3. Publish a content in space "A" and check if user X receive the notification. (He received. NOT OK)

Expected behavior

Blocked users shouldn't receive any email notification (except block/unblock message).

Screenshots

Notification received by a blocked user that should not have been received.

Stacktrace

No response

Extra data

• Device:
• Device OS:
• Browser:
• Decidim Version: 0.28
• Decidim installation:

Additional context

No response