Replace ActiveSupport's Object#to_query with own method

Having ActiveSupport as a dependency seems like overkill for doing
something so simple.
Replace constantize with Object.const_get

There is no point in using a third-party gem, especially ActiveSupport
which depends on everything, for something so simple.
Remove ActiveSupport as a runtime dependency

The two places where ActiveSupport methods were being used have been
modified to no longer require the module.
Merge branch 'technical/remove_active_support'