Add exactextract package

[giswqs]

Checklist

• [ ] Title of this PR is meaningful: e.g. "Adding my_nifty_package", not "updated meta.yaml".
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[conda-forge-webservices[bot]]

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

I wanted to let you know that I linted all conda-recipes in your PR (recipes/exactextract/meta.yaml) and found some lint.

Here's what I've got...

For recipes/exactextract/meta.yaml:

• Feedstock with the same name exists in conda-forge.