Add edit link to event details page

[trymebytes]

Fixes #365 and also displayed the notices on event details page using the wporg-notice block.

Before adding edit link

After adding edit link

Before using the notice block

After (using the notice block)

[amieiro]

In the "Edit event" button, I suggest you to maintain the same look and feel that we are using in the new buttons:

• Remove the icon.
• Add the square border.

Before

With the suggestion