There's a closed pull request on the void-packages repository

libproxy: update to 0.4.17.
https://github.com/void-linux/void-packages/pull/35515

Description:
- fix [CVE-2020-25219](https://nvd.nist.gov/vuln/detail/CVE-2020-25219)
- fix [CVE-2020-26154](https://nvd.nist.gov/vuln/detail/CVE-2020-26154)

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#### Testing the changes
- I tested the changes in this PR: **NO**

I don't know how to test this since there is almost no documentation on how to use `/usr/bin/proxy` but given there's no soname bump it should probably work fine.

Automated tests fail with same output on the old version.

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#### Local build testing
- I built this PR locally for my native architecture, (x86_64)
- I built this PR locally for these architectures (if supported. mark crossbuilds):
  - x86_64-musl
  - i686