Bug 29050: Added a punctuation between renewal messages

Bug 29050: Added a punctuation between renewal messages

Test plan:

1. First step is to go to administration > then system preferences
2. Set unseenrenewal to "allow"
3. Go to administatrion > circulation and fines rule
4. Set unseenrenewals count to any number
5. Check out an item to a patron and go to the checkouts tab
6. Renew the item
7. Notice that the renewal messages have no seperation
8. Apply the patch
9. Notice there is now a "&" in the spacing between renewal messages

Sponsored-by: Catalyst IT
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>