Add core/average.py/average_shape to ops/average.py

[charlesgauthier-udm]

Pull Request Checklist:

• [~] This PR addresses an already opened issue (for bug fixes / features)
  • This PR is related to this issue outside of clisops
• Tests for the changes have been added (for bug fixes / features)
• Documentation has been added / updated (for bug fixes / features)
• The new ops/average_shape is documented based on the other functions in ops/average.py, Please let me know if anything else needs to be added.
• HISTORY.rst has been updated (with summary of main changes)
• I have added my relevant user information to AUTHORS.md

What kind of change does this PR introduce?:

This PR exposes average_Shape from clisops/core to clisops/ops

Does this PR introduce a breaking change?:

Not to my knowledge

Other information:

As mentioned above, this PR is part of the work related to this issue outside of clisops

[github-actions]

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[coveralls]

Pull Request Test Coverage Report for Build 7277865257

• 10 of 23 (43.48%) changed or added relevant lines in 4 files are covered.
• No unchanged relevant lines lost coverage.
• Overall first build on savg at 72.348%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
clisops/core/average.py	1	2	50.0%
clisops/ops/average.py	7	19	36.84%

Totals
Change from base Build 7277603029:	72.3%
Covered Lines:	1732
Relevant Lines:	2394

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💛 - Coveralls

[huard]

Looks good.

This is unrelated to this PR, but I had some trouble with the installation of the dependencies. toolz and xarray required an upgrade after the conda env update.

[Zeitsperre]

@huard The reason for needing to perform an update after creating the environment is because more recent versions of xarray don't support some cftime objects (see: pydata/xarray#7794).

The workaround is to not install the latest xarray when using xESMF (not a great solution, but we weren't sure how else to proceed).

[Zeitsperre]

Congrats @charlesgauthier-udm !

I'll stage a new release, given that we now have some new functions from both you and Martin (@sol1105).