Fix the mafft recipes, they were a mess.

[dpryan79]

ℹ️
If this is your first pull request to Bioconda please ping @bioconda/core so it can be reviewed and to request being added as a member of the Bioconda team. Members of the Bioconda team are able to merge their own pull requests once tests and linting have passed.

---

• I have read the guidelines for bioconda recipes.
• This PR adds a new recipe.
• AFAIK, this recipe is directly relevant to the biological sciences (otherwise, please submit to the more general purpose conda-forge channel).
• This PR updates an existing recipe.
• This PR does something else (explain below).

[dpryan79]

Xref #15196

[biocondabot]

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

Arch	Package	Repodata
linux-64	mafft-7.310-hf484d3e_2.tar.bz2	repodata.json
linux-64	mafft-7.407-hf484d3e_2.tar.bz2	repodata.json
osx-64	mafft-7.310-h0a44026_2.tar.bz2	repodata.json
osx-64	mafft-7.407-h0a44026_2.tar.bz2	repodata.json

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You may alsu use conda to install these:

• For packages in linux-64:

  conda install -c https://56027-42372094-gh.circle-artifacts.com/0/tmp/artifacts/packages <package name>
  

• For packages in osx-64:

  conda install -c https://56029-42372094-gh.circle-artifacts.com/0/tmp/artifacts/packages <package name>
  

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Docker image(s) built:

Package	Tag	Install with docker
mafft	7.310--hf484d3e_2	show curl "https://56027-42372094-gh.circle-artifacts.com/0/tmp/artifacts/images/mafft%3A7.310--hf484d3e_2.tar.gz" | gzip -dc | docker load
mafft	7.407--hf484d3e_2	show curl "https://56027-42372094-gh.circle-artifacts.com/0/tmp/artifacts/images/mafft%3A7.407--hf484d3e_2.tar.gz" | gzip -dc | docker load