Document how to run macOS tests locally (#260)
Document how to run macOS tests locally (#260)

* Document how to run macOS tests locally

* Dan can't type

Co-authored-by: Nick Entin <0588e1bd5ce28f5b57295817473d9a4164365f5c@squareup.com>

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Co-authored-by: Nick Entin <0588e1bd5ce28f5b57295817473d9a4164365f5c@squareup.com>
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