fix(security): bump superagent dependency 3.5.2 -> 3.7.0

[shockey]

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Description of the PR

This PR bumps the pinned version for superagent to avoid CVE-2017-16129:

...superagent is vulnerable to ZIP bomb attacks. In a ZIP bomb attack, the HTTP server replies with a compressed response that becomes several magnitudes larger once uncompressed. If a client does not take special care when processing such responses, it may result in excessive CPU and/or memory consumption.