Add support for verifying version metadata with (one of) multiple keys

[dlon]

Close DES-1802.

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This change is 

[linear]

DES-1802 Support multiple trusted public keys

[MarkusPettersson98]

Reviewed 12 of 12 files at r1, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion

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mullvad-update/meta/src/platform.rs line 235 at r1 (raw file):

        // TODO: Actual key
        let public_key =
            key::VerifyingKey::from_hex(include_str!("../../test-pubkey")).expect("Invalid pubkey");

TODO: Actual keys* 😊

Code quote:

        // TODO: Actual key
        let public_key =
            key::VerifyingKey::from_hex(include_str!("../../test-pubkey")).expect("Invalid pubkey");

[dlon]

Reviewable status: 11 of 12 files reviewed, 1 unresolved discussion (waiting on @MarkusPettersson98)

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mullvad-update/meta/src/platform.rs line 235 at r1 (raw file):

Previously, MarkusPettersson98 (Markus Pettersson) wrote…

TODO: Actual keys* 😊

I've replaced this with the stagemole key, since it was inconsistent. But the TODO comment is unnecessary since we have an issue for this.

[MarkusPettersson98]

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved