fix: add a temporary exception for a new lint

ref: rust-lang/rust#82450

there will probably be a cleaner fix at some point (or even a change in
how the nightly cfg is implemented)

honeycomb-core/src/lib.rs

@@ -18,6 +18,7 @@
 // ------ CUSTOM LINTS
 
 // --- enable doc_auto_cfg feature if compiling in nightly
+#![allow(unexpected_cfgs)]
 #![cfg_attr(nightly, feature(doc_auto_cfg))]
 // --- some though love for the code
 #![warn(missing_docs)]