double-conversion v3.1.2

[regro-cf-autotick-bot]

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[conda-forge-linter]

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

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[xmnlab]

test wrong in the source. it was fixed in v3.1.3