ci(core): allowlist curve25519-dalek-derive

Proc-macro helper for curve25519-dalek (already allowlisted). Newer cargo
versions list it under `cargo tree --edges normal` while older ones do not;
the allowlist is a superset so it passes on both. Caught by core-deps-purity
on the first CI run of this branch.

Author: beardthelion

ci/gitlawb-core-allowed-deps.txt

@@ -47,6 +47,7 @@ crypto-common
 crypto_box
 crypto_secretbox
 curve25519-dalek
+curve25519-dalek-derive
 data-encoding
 data-encoding-macro
 data-encoding-macro-internal