ApplicationSettings analysis script does not support ActiveRecord::Encrypted

The following discussion from !176722 (closed) should be addressed:

• @mkaeppler started a discussion: (+1 comment)

  @rymai I ran scripts/cells/application-settings-analysis.rb and it sets this to false, even if the column is encrypted via ActiveRecord::Encryption. Maybe it does not support this yet?

When using encrypts, the script currently does not set the encrypted field correctly in the generated YAML. It only works for attr_encrypted, which we're phasing out.