Run core tests in Safari. Partially addresses https://github.com/pyodide/pyodide/issues/989

It runs, but there are several test failures, I'll open separate issues about those.
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---
name: Code improvement
about: Suggest a code improvement, i.e. refactoring, deprecation, etc.
title: ""
labels:
assignees: ""
---

## Proposed refactoring or deprecation

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