Description

This replaces calls to logger.warn with logger.warning. The former has been deprecated since Python 3.3 and generates DeprecationWarnings that can make output particularly in debugging and testing more noisy than necessary.

Sibling to conda/conda-build#5364.

Checklist - did you ...

As this is a purely internal change, I don't thing any of the following items apply.
However, it does remove the hack in gateways.logging to suppress the deprecation warnings.
Does that need special consideration?

• Add a file to the news directory (using the template) for the next release's release notes?
• Add / update necessary tests?
• Add / update outdated documentation?

Other repos

@jezdez noted that the same issue is present in other repos in the ecosystem.
They may be addressed in a similar manner and in detail are the following:

• conda/conda-index (Replace logger.warn w/ logger.warning conda-index#173)
• conda/conda-libmamba-solver (Replace logger.warn w/ logger.warning conda-libmamba-solver#476)
• conda/conda-lock (Replace logger.warn w/ logger.warning conda-lock#646)
• conda/conda-verify (Replace logger.warn w/ logger.warning conda-verify#115)
• conda/menuinst (Replace logger.warn w/ logger.warning menuinst#220)