Corrects an error when showing a suggestion linked to a deleted budget.

Corrects an error when showing a suggestion linked to a deleted budget.

If a suggestion is associated to a budget that was deleted, an error was
returned because we try to get the name of a budget that doesn't exist.
With this fix, the page is shown without errors.

Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
(cherry picked from commit 0a43ba114d0fee9a478def455b926121442a0814)

Signed-off-by: Chris Nighswonger <chris.nighswonger@gmail.com>