Update mhcnuggets to 2.3.1

[BiocondaBot]

Update mhcnuggets: 2.2 → 2.3.1

Info	Link
Recipe	recipes/mhcnuggets (click to view/edit other files)
Releases	https://pypi.org/pypi/mhcnuggets/json

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This pull request was automatically generated (see docs).

[biocondabot]

Package(s) built on CircleCI are ready for inspection:

Arch	Package	Repodata
noarch	mhcnuggets-2.3.1-py_0.tar.bz2	repodata.json

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You may also use conda to install these:

• For packages in noarch:

  conda install -c https://61997-42372094-gh.circle-artifacts.com/0/tmp/artifacts/packages <package name>
  

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Docker image(s) built:

Package	Tag	Install with docker
mhcnuggets	2.3.1--py_0	show curl "https://61997-42372094-gh.circle-artifacts.com/0/tmp/artifacts/images/mhcnuggets%3A2.3.1--py_0.tar.gz" | gzip -dc | docker load

[druvus]

@bioconda-bot recheck