Upgrading a few dependencies with cargo audit warnings

[faern]

As far as I could understand none of these upgrades really affected us. But best to stay with up to date software.

rand_core: https://rustsec.org/advisories/RUSTSEC-2021-0023
hyper: https://rustsec.org/advisories/RUSTSEC-2021-0020
Why pin-project-lite was yanked: taiki-e/pin-project-lite#55

Git checklist:

• Describe the change in CHANGELOG.md under the [Unreleased] header.
• Check that commits follow the Mullvad coding guidelines

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This change is 

[dlon]

Reviewed 1 of 1 files at r1.
Reviewable status: complete! all files reviewed, all discussions resolved