Reduce noise of exclusive lease lock for atomic processing service

What does this MR do and why?

This MR changes the log level to :info for exclusive lease logs. This is because previously this was :error and leads to a lot of red herrings among customers and supports.

These log errors are actually ok because when the lease is occupied the previous job will still be processing and will handle subsequent changes.

Screenshots or screen recordings

N/A

Before	After

How to set up and validate locally

N/A - as this only sometimes occurs it's hard to test locally

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #331033 (closed)