Suppress unknown_lints lint

src/bin/fish_indent.rs

@@ -2,6 +2,7 @@
 
 // Delete this once we require Rust 1.74.
 #![allow(unstable_name_collisions)]
+#![allow(unknown_lints)]
 #![allow(clippy::uninlined_format_args)]
 #![allow(clippy::incompatible_msrv)] // false positive for is_some_and (we have a polyfill)
 

src/lib.rs

@@ -3,6 +3,7 @@
 #![allow(non_camel_case_types)]
 #![allow(non_upper_case_globals)]
 #![allow(unstable_name_collisions)]
+#![allow(unknown_lints)] // prevent stable from complaining about nightly-only lints
 #![allow(clippy::bool_assert_comparison)]
 #![allow(clippy::box_default)]
 #![allow(clippy::collapsible_if)]