add packaging dep

[jhamman]

closes #71

xref: https://github.com/pydata/xarray/pull/6207

Checklist

• [x] Used a personal fork of the feedstock to propose changes
• [x] Bumped the build number (if the version is unchanged)
• [x] Re-rendered with the latest conda-smithy (Use the phrase code>@<space/conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• [x] Ensured the license file is being packaged.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[jhamman]

@conda-forge-admin, please rerender

[github-actions[bot]]

Hi! This is the friendly automated conda-forge-webservice.

I tried to rerender for you, but it looks like there was nothing to do.

This message was generated by GitHub actions workflow run https://github.com/conda-forge/xarray-feedstock/actions/runs/1769909751.

[ocefpaf]

@conda-grayskull show requirements

[conda-grayskull]

Working on your request...

[conda-grayskull]

================ HOST ================ Requirements for host	Current Deps	Grayskull found
python >=3.8	python >=3.8	:heavy_check_mark:
pip	pip	:heavy_check_mark:
setuptools_scm		:x:
	setuptools-scm	:heavy_plus_sign:

================ RUN ================ Requirements for run	Current Deps	Grayskull found
python >=3.8	python >=3.8	:heavy_check_mark:
numpy >=1.18	numpy >=1.18	:heavy_check_mark:
pandas >=1.1	pandas >=1.1	:heavy_check_mark:
importlib_metadata		:x:
typing_extensions >=3.7		:x:
packaging >=20.0		:x:

[ocefpaf]

@marcelotrevisani we have setuptools_scm but the bot suggested setuptools-scm. We need to standardized that. Packaing was found but importlib_metadata and typing_extensions >=3.7 probably have conditionals. I'll check later.

@jhamman sorry to hijack your PR but I wanted to take our new bot for a spin. This one is good to be merged!