🎩 What? Why?

While working with an app and disabling the decidim-elections module, I found a data migration that doesn't work. This PR fixes it by following the strategy 3 from #8068 (Define ad-hoc model classe)

Testing

To check the failure:

1. Comment decidim-elections gem from development_app/Gemfile
2. Run bundle install
3. Regenerate and migrate the DB: bin/rails db:drop db:create db:migrate

See the exception:
== 20240125096051 AddFollowableCounterCacheToVotings: migrating ===============
-- add_column(:decidim_votings_votings, :follows_count, :integer, {:null=>false, :default=>0, :index=>true})
-> 0.0011s
rails aborted!
StandardError: An error has occurred, this and all later migrations canceled: (StandardError)

uninitialized constant Decidim::Votings
/home/apereira/Work/decidim/decidim/development_app/db/migrate/20240125096051_add_followable_counter_cache_to_votings.decidim_elections.rb:10:in block (2 levels) in change' /home/apereira/Work/decidim/decidim/development_app/db/migrate/20240125096051_add_followable_counter_cache_to_votings.decidim_elections.rb:9:in block in change'
/home/apereira/Work/decidim/decidim/development_app/db/migrate/20240125096051_add_followable_counter_cache_to_votings.decidim_elections.rb:8:in change' /home/apereira/Work/decidim/decidim/development_app/bin/rails:5:in <top (required)>'
/home/apereira/Work/decidim/decidim/development_app/bin/spring:10:in block in <top (required)>' /home/apereira/Work/decidim/decidim/development_app/bin/spring:7:in <top (required)>'

Caused by:
NameError: uninitialized constant Decidim::Votings (NameError)

    Decidim::Votings::Voting.reset_column_information
                    ^^^^^^^^

/home/apereira/Work/decidim/decidim/development_app/db/migrate/20240125096051_add_followable_counter_cache_to_votings.decidim_elections.rb:10:in block (2 levels) in change' /home/apereira/Work/decidim/decidim/development_app/db/migrate/20240125096051_add_followable_counter_cache_to_votings.decidim_elections.rb:9:in block in change'
/home/apereira/Work/decidim/decidim/development_app/db/migrate/20240125096051_add_followable_counter_cache_to_votings.decidim_elections.rb:8:in change' /home/apereira/Work/decidim/decidim/development_app/bin/rails:5:in <top (required)>'
/home/apereira/Work/decidim/decidim/development_app/bin/spring:10:in block in <top (required)>' /home/apereira/Work/decidim/decidim/development_app/bin/spring:7:in <top (required)>'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)

To fix it:

1. Apply this patch
2. Remove the migration rm development_app/db/migrate/*_add_followable_counter_cache_to_votings.decidim_elections.rb
3. Copy the new migration bin/rails decidim:update
4. Migrate bin/rails db:migrate

♥️ Thank you!