LP#2051250: restore bold styling in PO summary when PO is paid off

LP#2051250: restore bold styling in PO summary when PO is paid off

This patch fixes a regression on bug 1999270 introduced by a patch
for bug 2000482.

To test
-------
[1] Create a purchase order whose full amount is paid off.
[2] View the order and note that the '$X Paid' text is red but not bold.
[3] Apply the patch and review the order again. This time, the text
    in the PO summary should also be bold.

Release-note: Restore bold styling of paid off amount in purchase order summary.

Signed-off-by: Galen Charlton <gmc@equinoxOLI.org>
Signed-off-by: Jane Sandberg <sandbergja@gmail.com>
Signed-off-by: Stephanie Leary <stephanie.leary@equinoxoli.org>