CLOUD-809: chore(aurora clone lambda) update from python 3.10 to 3.14

[ruthwells]

Describe your changes

Python 3.10 is deprecated - this PR upgrades the lambdas used by the aurora clone mechanism to Python 3.14.

Checklist before requesting a review

• I have performed a self-review of my code
• I have updated the Readme / docs
• If this is a breaking change, I have discussed the roll-out and roll-back plan with the team(s) and I have provided detailed instructions.

I've done a search of citizensadvice github repos, and the only repo that uses the AuroraCloneRefresh construct is casebook (and the now dead witnessbox-v2). This is only in staging/preprod, so we will be able to test before releasing changes to production. I will communicate/manage this with the adviser engineers.

EDIT: @mlaycock @Slange-Mhath @MrJoosh I think this PR (once the version of ca-cdk-constructs is updated in the casebook repo) will also fix the EOL lambdas in the cita-devops account for the qa-DevCasebookDataExtractor. But my AWS permissions don't allow me to see if there are also any aurora clones in the cab-data-prod account 445513191207.

• If it is a core feature, I have added thorough tests

[simonwgill]

I don't like that there's no automated tests for this code at all... and that the lambda code can be run under a different runtime than the one used for any static type checking.

But since that's been the case forever and it's not used for any production infrastructure, I guess it's a case of send it, and see if the unlikely case of a failure breaks something.

[Slange-Mhath]

lgtm and thanks for doing this Ruth!

[MrJoosh]

LGTM - we don't have any clones in cab-data-prod so all good from our side! Thanks Ruth!