feat: Removed ben and added k9ert keys for releasing #306
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The installation and update process is done with two different binaries. Both binaries contain pubkeys which makes it possible to check signatures on the device when upgrading.
This PR is removing Ben's key and it's adding k9ert's key. It gets checked with each update. That means that this PR gets relevant for new installations with a new release and for upgrades one release after.
This release is ugrading the specter-bootloader from fc6e61 to 6e727 which contains 2 PRs:
Most of the files come from the test PR in the test directory. The relevant change is in the
pubkeys.c. The xpubconvert.py tool can be used to convert an xpub to the format needed in thepubkeys.c.