gnu: Remove rust-diffus-derive-0.10.

* gnu/packages/crates-io.scm (rust-diffus-derive-0.10): Delete variable.

gnu/packages/crates-io.scm

@@ -17048,30 +17048,6 @@ common subsequence.  The diff algorithms include Myer's diff and Patience
 diff.")
     (license (list license:asl2.0 license:expat))))
 
-(define-public rust-diffus-derive-0.10
-  (package
-    (name "rust-diffus-derive")
-    (version "0.10.0")
-    (source
-     (origin
-       (method url-fetch)
-       (uri (crate-uri "diffus-derive" version))
-       (file-name
-        (string-append name "-" version ".tar.gz"))
-       (sha256
-        (base32 "1a7sgbzhqa7gk3xhvkci91myc86gkwxs04vfxbl8f64y7l1jsfmr"))))
-    (build-system cargo-build-system)
-    (arguments
-     `(#:cargo-inputs
-       (("rust-proc-macro2" ,rust-proc-macro2-1)
-        ("rust-quote" ,rust-quote-1)
-        ("rust-syn" ,rust-syn-1))))
-    (home-page "https://github.com/distil/diffus")
-    (synopsis "Diff two instances of any data structure")
-    (description "This package finds the difference between two instances of
-any data structure.  Supports derive on structs and enums.")
-    (license license:asl2.0)))
-
 (define-public rust-digest-0.10
   (package
     (name "rust-digest")