gnu: cl-environments: Update to 20200401.

* gnu/packages/lisp-xyz.scm (cl-environments): Update to 20200401.
This includes the :tools package not present in 0.2.3.

gnu/packages/lisp-xyz.scm

@@ -14376,36 +14376,37 @@ collecting values easier.")
 (define-public cl-environments
   ;; TODO: asdf-build-system/sbcl fails here, why?  See if it works with the
   ;; build system revamp once staging is merged after 2020-11-09.
-  (package
-    (name "cl-environments")
-    (version "0.2.3")
-    (source
-     (origin
-       (method git-fetch)
-       (uri (git-reference
-             (url "https://github.com/alex-gutev/cl-environments")
-             (commit (string-append "v" version))))
-       (file-name (git-file-name name version))
-       (sha256
-        (base32
-         "08w364if2ivxwdarz44vwk0s61zk8l8pnrwskaghbrjg3his1nmd"))))
-    (build-system asdf-build-system/source)
-    (propagated-inputs
-     `(("alexandria" ,sbcl-alexandria)
-       ("anaphora" ,sbcl-anaphora)
-       ("collectors" ,sbcl-collectors)
-       ("optima" ,sbcl-optima)))
-    (native-inputs
-     `(("prove" ,sbcl-prove)
-       ("prove-asdf" ,sbcl-prove-asdf)))
-    (home-page "https://github.com/alex-gutev/cl-environments")
-    (synopsis "Implements the Common Lisp standard environment access API")
-    (description "This library provides a uniform API, as specified in Common
+  (let ((commit "bbcd958a9ff23ce3e6ea5f8ee2edad9634819a3a")) ; No version in 2 years.
+    (package
+      (name "cl-environments")
+      (version (git-version "0.2.3" "1" commit))
+      (source
+       (origin
+         (method git-fetch)
+         (uri (git-reference
+               (url "https://github.com/alex-gutev/cl-environments")
+               (commit commit)))
+         (file-name (git-file-name name version))
+         (sha256
+          (base32
+           "1pfxl3vcdrb4mjy4q4c3c7q95kzv6rfjif3hzd5q91i9z621d64r"))))
+      (build-system asdf-build-system/source)
+      (propagated-inputs
+       `(("alexandria" ,cl-alexandria)
+         ("anaphora" ,cl-anaphora)
+         ("collectors" ,cl-collectors)
+         ("optima" ,cl-optima)))
+      (native-inputs
+       `(("prove" ,sbcl-prove)
+         ("prove-asdf" ,sbcl-prove-asdf)))
+      (home-page "https://github.com/alex-gutev/cl-environments")
+      (synopsis "Implements the Common Lisp standard environment access API")
+      (description "This library provides a uniform API, as specified in Common
 Lisp the Language 2, for accessing information about variable and function
 bindings from implementation-defined lexical environment objects.  All major
 Common Lisp implementations are supported, even those which don't support the
 CLTL2 environment access API.")
-    (license license:expat)))
+      (license license:expat))))
 
 (define-public sbcl-static-dispatch
   (package