Revert "Merge branch '550805-allow-admins-to-choose-adapter' into 'master' "

What does this MR do and why?

Resolve "TCP connections from GitLab processes ... (!204437 - merged) caused an error in the ActiveContext::BulkProcessWorker. See error details

This MR reverts the changes from !204437 (merged).

Checklist

• Create an issue to reinstate the merge request and assign it to the author of the reverted merge request.
• If the revert is to resolve a broken 'master' incident, please read through the Responsibilities of the Broken master resolution DRI.
• If the revert involves a database migration, please read through Deleting existing migrations.
• Add the appropriate labels before the MR is created. We can skip CI/CD jobs only if the labels are added before the CI/CD pipeline is created.

Milestone info

• I am reverting something in the current milestone. No changelog is needed, and I've added a ~"regression:*" label.
• I am reverting something in a different milestone. A changelog is needed, and I've removed the ~"regression:*" label.

Screenshots or screen recordings

N/A

How to set up and validate locally

Validation steps

hashes = [elasticsearch,document,ids,from,gitlab_active_context_code,index]
::Ai::ActiveContext::Collections::Code.track_refs!(routing: "1", hashes: hashes)

# check to determine which queue the hashes are added
ActiveContext::Queues.all_queued_items

# process the relevant queue
::Ai::ActiveContext::BulkProcessWorker.new.perform("Ai::ActiveContext::Queues::Code", <queue number>)

Before revert - there is an error

::Ai::ActiveContext::BulkProcessWorker.new.perform("Ai::ActiveContext::Queues::Code", <queue number>)
=> NameError: wrong constant name typhoeus
from /Users/pamartiaga/.local/share/mise/installs/ruby/3.3.9/lib/ruby/gems/3.3.0/gems/faraday-2.13.4/lib/faraday/adapter_registry.rb:20:in `const_get'

After revert - there is NO error

::Ai::ActiveContext::BulkProcessWorker.new.perform("Ai::ActiveContext::Queues::Code", <queue number>)
=> [1, 1]

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.