Ensure we don't have leftover columns after loading

This will prevent fetching useless fields, and potentially off by 1 or
more when loading entities after a database change
4 jobs for check_number_of_columns in 11 minutes and 13 seconds (queued for 1 second)
Status Job ID Name Coverage
  Test
passed #284055
amd64 debian
asan-ubsan

00:11:02

passed #284052
amd64 debian
linux

00:09:06

passed #284053
win32
win32

00:11:13

passed #284054
win64
win64

00:09:54