gnu: flex: Update bison-for-tests to 3.0.5.

* gnu/packages/flex.scm (flex)[inputs]: Make BISON-FOR-TESTS inherit source
from BISON, and disable tests on it since they require flex.

gnu/packages/flex.scm

@@ -45,22 +45,10 @@
     (build-system gnu-build-system)
     (inputs
      (let ((bison-for-tests
-            ;; Work around an incompatibility with Bison 3.0:
-            ;; <http://lists.gnu.org/archive/html/bug-bison/2013-09/msg00014.html>.
             (package
               (inherit bison)
-              (version "2.7.1")
-              (source (origin
-                        (method url-fetch)
-                        (uri (string-append
-                              "mirror://gnu/bison/"
-                              "bison-" version ".tar.xz"))
-                        (sha256
-                         (base32
-                          "1yx7isx67sdmyijvihgyra1f59fwdz7sqriginvavfj5yb5ss2dl"))))
-
-              ;; Unlike Bison 3.0, this version did not need Flex for its
-              ;; tests, so it allows us to break the cycle.
+              ;; Disable tests, since they require flex.
+              (arguments '(#:tests? #f))
               (inputs (alist-delete "flex" (package-inputs bison))))))
        `(("bison" ,bison-for-tests)
          ("indent" ,indent))))