79539fbfbf guix: update signapple (fanquake)
Pull request description:
Fixes#28449, and removes the need to boostrap Rust, by avoiding the `python-requests` dependency.
Comparing a `--no-substitutes` build of this PR, to master, signapple requires ~1350 _less_ packages to boostrap:
Master derivation - https://gist.github.com/fanquake/dbf69a62c9a78b7ae8c183a160e6d58d
PR derivation - https://gist.github.com/fanquake/0aa2d8eddaba861ba489ed3d936f727d
ACKs for top commit:
achow101:
ACK 79539fbfbf
Tree-SHA512: 341ddcae27e53c31d114465cb5173573dcc9e1c0874ee160715630f686da6f69255f6080ec0181ffeffc26efbdb545599d667784b1cd17dfa7e3da0998ec9bd6