Add `Locale` conversion format configuration property

[scordio]

Overview

Fixes #3141.

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Definition of Done

• [ ] There are no TODOs left in the code
• [ ] Method preconditions are checked and documented in the method's Javadoc
• [ ] Coding conventions (e.g. for logging) have been followed
• [ ] Change is covered by automated tests including corner cases, errors, and exception handling
• [ ] Public API has Javadoc and @API annotations
• [ ] Change is documented in the User Guide and Release Notes

[scordio]

Waiting for #3507 to be finalized before moving forward.