gnu: Add rust-rustc-ap-rustc-lexer-721.

* gnu/packages/crates-io.scm (rust-rustc-ap-rustc-lexer-721): New variable.
(rust-rustc-ap-rustc-lexer-654): inherit from above.

Signed-off-by: Nicolas Goaziou <mail@nicolasgoaziou.fr>

gnu/packages/crates-io.scm

@@ -36003,8 +36003,36 @@ It is automatically published using the compiler repository at
 @url{https://www.github.com/rust-lang/rust}")
     (license (list license:expat license:asl2.0))))
 
+(define-public rust-rustc-ap-rustc-lexer-721
+  (package
+    (name "rust-rustc-ap-rustc-lexer")
+    (version "721.0.0")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (crate-uri "rustc-ap-rustc_lexer" version))
+       (file-name
+        (string-append name "-" version ".tar.gz"))
+       (sha256
+        (base32
+         "1ldk41a4vxgh39p9650vhw1j7fng06pfmvb4xb2pvp22547gd89b"))))
+    (build-system cargo-build-system)
+    (arguments
+     `(#:cargo-inputs
+       (("rust-unicode-xid" ,rust-unicode-xid-0.2))
+       #:cargo-development-inputs
+       (("rust-expect-test" ,rust-expect-test-1))))
+    (home-page "https://github.com/alexcrichton/rustc-auto-publish")
+    (synopsis "Automatically published versions of rustc macros")
+    (description
+     "Use the lexer used in the Rust compiler with this crate.
+It is automatically published using the compiler repository at
+@url{https://www.github.com/rust-lang/rust}.")
+    (license (list license:expat license:asl2.0))))
+
 (define-public rust-rustc-ap-rustc-lexer-654
   (package
+    (inherit rust-rustc-ap-rustc-lexer-721)
     (name "rust-rustc-ap-rustc-lexer")
     (version "654.0.0")
     (source
@@ -36016,17 +36044,9 @@ It is automatically published using the compiler repository at
        (sha256
         (base32
          "19bx2z4gxxzqfjh9m11jp52lgdzz0k5fb0p1ad739bdc5cm4sciv"))))
-    (build-system cargo-build-system)
     (arguments
      `(#:cargo-inputs
-       (("rust-unicode-xid" ,rust-unicode-xid-0.2))))
+       (("rust-unicode-xid" ,rust-unicode-xid-0.2))))))
-    (home-page "https://github.com/alexcrichton/rustc-auto-publish")
-    (synopsis "Automatically published versions of rustc macros")
-    (description
-     "Use the lexer used in the Rust compiler with this crate.
-It is automatically published using the compiler repository at
-@url{https://www.github.com/rust-lang/rust}.")
-    (license (list license:expat license:asl2.0))))
 
 (define-public rust-rustc-ap-rustc-macros-654
   (package