Bug 6056: Notes were not shown when modifying order line

Bug 6056: Notes were not shown when modifying order line

To test:
- add a new order in acquisitions with some content in the notes field
- save order
- modify order - Notes field will be shown as empty

The template variable for notes is missing from the template.

Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
(cherry picked from commit 9cab9be3d6114898e0b8354d784fb8d56ad51fbc)

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