Bug 20773: (bug 20724 follow-up) Add a simple db revision

Bug 20773: (bug 20724 follow-up) Add a simple db revision

We should correct bad data too.
This is a trivial, pragmatic approach. Instead of doing a complex
calculation with holidays etc. (as was done on 12063), we just add
MaxPickupDelay or 7 days to today probably resulting in a little bonus
time. Only for waiting holds. When the ReservesNeedReturns pref was not
Automatic, there should be no changes.

== Test plan ==
1. git checkout c585f1149770ec401f188e061211501897cec0bf~1
     This the commit before bug 20724's patches.
     We need that to be able to generate "corrupted data"
2. Set ReservesNeedReturns to "Automatically"
3. Place a hold on a specific item
4. The hold should have an *empty* expiration date
     record page → Hold → "Expiration" column
5. Apply this patch
6. Run updatedatabase.pl
7. Refresh the page
8. The hold should have an expiration date (not empty)
9. Celebrate! 🎉🎊🥳

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Victor Grousset <victor.grousset@biblibre.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Bug 20773: (followup) Remove MySQLism

Signed-off-by: Victor Grousset <victor.grousset@biblibre.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>