fix takeover cgi script

if last_backup was an int, the script failed with this error:

result undefined, global datetime = <module 'datetime' from '/srv/slapgrid/
slappart6...6d33cee74/lib/python2.7/lib-dynload/datetime.so'>,
datetime.datetime = <type 'datetime.datetime'>,
datetime.datetime.fromtimestamp = <built-in method fromtimestamp of type
object>, last_backup = '1587724103'
<type 'exceptions.TypeError'>: a float is required
      args = ('a float is required',)
      message = 'a float is required'

stack/resilient/buildout.hash.cfg

@@ -46,7 +46,7 @@ md5sum = d21472f0e58f928fb827f2cbf22c4d4a
 
 [resilient-web-takeover-cgi-script-download]
 filename = resilient-web-takeover-cgi-script.py.in
-md5sum = a7d6ca463e4b6438e1d826f531533a39
+md5sum = 7a0f1be7e9d05d0c68748322abe1f511
 
 [template-wrapper]
 filename = templates/wrapper.in

stack/resilient/resilient-web-takeover-cgi-script.py.in

@@ -53,7 +53,7 @@ def getLatestBackupDate():
       timestamp = float(db[callback])
       if timestamp > last_backup:
         last_backup = timestamp
-    result = datetime.datetime.fromtimestamp(last_backup)
+    result = datetime.datetime.fromtimestamp(float(last_backup))
   db.close()
   shutil.rmtree(temporary_directory)
   return result