Fix Active Record's connection_pool_list deprecation warning for Rails 7.1.x

[eiskrenkov]

Fixes deprecation warning for Rails 7.1.x

DEPRECATION WARNING: connection_pool_list currently only applies to connection pools in the current role (writing). In Rails 7.2, this method will apply to all known pools, regardless of role. To affect only those connections belonging to a specific role, pass the role name as an argument. To switch to the new behavior, pass :all as the role name.

The deprecation is coming from here and was introduced here

Passing ActiveRecord::Base.current_role to connection_pool_list just preserves current behaviour while silencing the deprecation warning

[eiskrenkov]

I have signed the CLA!

[eiskrenkov]

@jenshenny @dylanahsmith can you please check this out? CI failures seem to be not related to my changes

[casperisfine]

CI is broken, I'll fix it on another PR.

[pboling]

How can one "temporarily deploy to rubygems"? 😆