Partially addresses #47424.

This cop has been renamed to ActiveRecordSerialize to match the way
"ActiveRecord" is usually written.

This Cop blacklists the use of ActiveRecord's "serialize" method, except
for cases where we already use this.

This reverts commit 3e991230.

# Conflicts:
#	app/models/project.rb

In 8278b763 the default behaviour of annotation
has changes, which was causing a lot of noise in diffs. We decided in #17382
that it is better to get rid of the whole annotate gem, and instead let people
look at schema.rb for the columns in a table.

Fixes: #17382