gnu: rust-rctree: Add 0.4.

* gnu/packages/crates-io.scm (rust-rctree-0.4): New variable.
(rust-rctree-0.3): Inherit from it.

gnu/packages/crates-io.scm

@@ -48088,19 +48088,18 @@ Rust.")
     (description "This package provides core APIs for Rayon.")
     (license (list license:asl2.0 license:expat))))
 
-(define-public rust-rctree-0.3
+(define-public rust-rctree-0.4
   (package
     (name "rust-rctree")
-    (version "0.3.3")
+    (version "0.4.0")
     (source
       (origin
         (method url-fetch)
         (uri (crate-uri "rctree" version))
-        (file-name
-         (string-append name "-" version ".tar.gz"))
+        (file-name (string-append name "-" version ".tar.gz"))
         (sha256
          (base32
-          "1a54z2b850albiqx9vw009p9xg363vqzh1ybkwb89zn8375jk7my"))))
+          "1s92472lniqn2c0b5ln8ssl014x0raiyzkk0hagrvsd6far2iq4s"))))
     (build-system cargo-build-system)
     (home-page "https://github.com/RazrFalcon/rctree")
     (synopsis "DOM-like tree implemented using reference counting")
@@ -48108,6 +48107,20 @@ Rust.")
 reference counting.")
     (license license:expat)))
 
+(define-public rust-rctree-0.3
+  (package
+    (inherit rust-rctree-0.4)
+    (name "rust-rctree")
+    (version "0.3.3")
+    (source
+      (origin
+        (method url-fetch)
+        (uri (crate-uri "rctree" version))
+        (file-name (string-append name "-" version ".tar.gz"))
+        (sha256
+         (base32
+          "1a54z2b850albiqx9vw009p9xg363vqzh1ybkwb89zn8375jk7my"))))))
+
 (define-public rust-rdrand-0.4
   (package
     (name "rust-rdrand")