Add miniconda 4.11.0

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  • Closes https://github.com/pyenv/pyenv/issues/XXXX

Description

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I used add_miniconda.py to generate installation files for miniconda3-3.7-4.11.0, miniconda3-3.8-4.11.0, and miniconda3-3.9-4.11.0.

Tests

• My PR adds the following unit tests (if any)