Hide create project tile for some users

What does this MR do and why?

Relates to #334121 (closed)

For users unable to create projects, the welcome state includes a tile with a title Create a project. The tile, however, it is not clickable and it is not grey-out (to show that the tile is inactive).

There are two type of users unable to create projects:

• External users

• Regular users whose Projects limit setting has been set to zero

Here, we replace the create project tile by an alert.

Screenshots or screen recordings

Before

After

For an external user:

For a regular user unable to create projects:

How to set up and validate locally

1. As an admin, create an external user and a user with a zero Projects limit: https://gdk.test:3443/admin/users/new
2. Impersonate these users

MR acceptance checklist

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