Update Method Calls that use the Connection Pool Gem

[kevinreiss]

What maintenance needs to be done?

Update the way arguments are passed to calls to the connection_pool gem to a way that compiles with version 3.x of the gem.

Level of urgency

• High
• Moderate
• Low

Why is this maintenance needed?

• We are now pinned to an old version of the gem.

Acceptance criteria

• We can run the connection_pool gem version 3.x without any errors.
• We remove pin to v 2.4 of the gem add in this PR.

Implementation notes, if any

Review our code for the pattern that will work with the connection_pool v. 3.x gem.
https://github.com/mperham/connection_pool/blob/35ea6ce887edf495e9c15322927ccce84249bcd3/lib/connection_pool/timed_stack.rb#L63 vs
https://github.com/mperham/connection_pool/blob/f0d6dd2ab7241132a5bce4845d011a66786bad2c/lib/connection_pool/timed_stack.rb#L62

resolves https://app.honeybadger.io/projects/54497/faults/126323333