the default binds for exec_query should be [] not nil, for compatibility with the real connection adapters
Revert "fixing import of marginalia into inactive connection adapters".  it was problematic because it causes ActiveRecord to actually make the connection to the database - straight away when the gem loads, before any other gems etc. have had a chance to hook the database connection class.  the commit message doesn't explain why this was done, and it works without doing it.

This reverts commit 43c93e2aca4deff72fc72ef7c64a751da162ec9b.