Bug 34910: (follow-up) alert in patron details

Bug 34910: (follow-up) alert in patron details

The anonymous patron details page should show an alert message.

1) Configure an existing borrowernumber in system preference 'AnonymousPatron'
2) Go to details page of this borrower :
   /cgi-bin/koha/members/moremember.pl?borrowernumber=x
3) Check you see alert 'This is the anonymous patron.'

Signed-off-by: Kelly McElligott <kelly@bywatersolutions.com>
Signed-off-by: Johanna Miettunen <johanna.miettunen@haaga-helia.fi>
Signed-off-by: Päivi Knuutinen <paivi.knuutinen@joensuu.fi>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>