Use the rustc unknown lints attribute

The clippy unknown lints attribute was deprecated in
nightly in rust-lang/rust#80524. The old lint name now produces a
warning.

Since we're using `allow(unknown_lints)` to suppress warnings, we need to
adopt the canonical name, so we can continue to build without warnings.

This change was automatically generated using the following script:

```sh
sd clippy::unknown_clippy_lints unknown_lints \
   $(fd . --extension rs zebra*)`
```

zebra-chain/src/lib.rs

@@ -9,7 +9,7 @@
 // #![deny(missing_docs)]
 #![allow(clippy::try_err)]
 // Disable some broken or unwanted clippy nightly lints
-#![allow(clippy::unknown_clippy_lints)]
+#![allow(unknown_lints)]
 #![allow(clippy::from_iter_instead_of_collect)]
 #![allow(clippy::unnecessary_wraps)]
 

zebra-consensus/src/lib.rs

@@ -37,7 +37,7 @@
 //#![deny(missing_docs)]
 #![allow(clippy::try_err)]
 // Disable some broken or unwanted clippy nightly lints
-#![allow(clippy::unknown_clippy_lints)]
+#![allow(unknown_lints)]
 #![allow(clippy::unnecessary_wraps)]
 
 mod block;

zebra-network/src/lib.rs

@@ -39,7 +39,7 @@
 // https://github.com/tokio-rs/tracing/issues/553
 #![allow(clippy::cognitive_complexity)]
 // Disable some broken or unwanted clippy nightly lints
-#![allow(clippy::unknown_clippy_lints)]
+#![allow(unknown_lints)]
 #![allow(clippy::unnecessary_wraps)]
 
 #[macro_use]

zebra-script/src/lib.rs

@@ -3,7 +3,7 @@
 #![doc(html_logo_url = "https://www.zfnd.org/images/zebra-icon.png")]
 #![doc(html_root_url = "https://doc.zebra.zfnd.org/zebra_script")]
 // Disable some broken or unwanted clippy nightly lints
-#![allow(clippy::unknown_clippy_lints)]
+#![allow(unknown_lints)]
 #![allow(clippy::unnecessary_wraps)]
 
 use displaydoc::Display;

zebra-state/src/lib.rs

@@ -6,7 +6,7 @@
 #![warn(missing_docs)]
 #![allow(clippy::try_err)]
 // Disable some broken or unwanted clippy nightly lints
-#![allow(clippy::unknown_clippy_lints)]
+#![allow(unknown_lints)]
 #![allow(clippy::field_reassign_with_default)]
 #![allow(clippy::unnecessary_wraps)]
 

zebra-test/src/lib.rs

@@ -1,7 +1,7 @@
 //! Miscellaneous test code for Zebra.
 
 // Disable some broken or unwanted clippy nightly lints
-#![allow(clippy::unknown_clippy_lints)]
+#![allow(unknown_lints)]
 #![allow(clippy::from_iter_instead_of_collect)]
 // Each lazy_static variable uses additional recursion
 #![recursion_limit = "256"]

zebrad/tests/acceptance.rs

@@ -16,7 +16,7 @@
 #![allow(dead_code)]
 #![allow(clippy::try_err)]
 // Disable some broken or unwanted clippy nightly lints
-#![allow(clippy::unknown_clippy_lints)]
+#![allow(unknown_lints)]
 #![allow(clippy::field_reassign_with_default)]
 
 use color_eyre::eyre::Result;