LP1915440 Clear Hopeless Date on Capture

LP1915440 Clear Hopeless Date on Capture

Clear the hold hopeless date when a copy is captured for the hold.

One way to make this happen for testing:

. Configure the Missing copy status as holdable=true hopeless_prone=true
. Place hold with only 1 viable copy.
. Mark said copy as missing -- this stamps a hopeless_date on the hold.
. Check the copy in.  This results in a capture + hopeless hold.

Signed-off-by: Bill Erickson <berickxx@gmail.com>