gnu: Remove redundant wrapping from packages using ruby-build-system.

Now that the build system does wrapping automatically, it can be removed from
the packages that do it manually.

* gnu/packages/databases.scm (es-dump-restore)[arguments]: Remove #:phases.
* gnu/packages/ruby.scm (ruby-redcloth)[arguments]: Remove #:phases.
  (ruby-httpclient)[arguments]: Remove 'wrap-bin-httpclient from the modified
  phases.

gnu/packages/databases.scm

@@ -291,18 +291,7 @@ (define-public es-dump-restore
          "020yk7f1hw48clmf5501z3xv9shsdchyymcv0y2cci2c1xvr1mim"))))
     (build-system ruby-build-system)
     (arguments
-     '(#:tests? #f ;; No testsuite.
+     '(#:tests? #f)) ;; No testsuite.
-       #:phases
-       (modify-phases %standard-phases
-         (add-after 'install 'wrap-bin-es_dump_restore
-           (lambda* (#:key outputs #:allow-other-keys)
-             (wrap-program (string-append (assoc-ref outputs "out")
-                                          "/bin/es_dump_restore")
-               `("GEM_PATH" ":" prefix (,(getenv "GEM_PATH")
-                                        ,(string-append
-                                          (assoc-ref outputs "out")
-                                          "/lib/ruby/vendor_ruby"))))
-             #t)))))
     (propagated-inputs
      `(("ruby-httpclient" ,ruby-httpclient)
        ("ruby-multi-json" ,ruby-multi-json)

gnu/packages/ruby.scm

@@ -2852,17 +2852,7 @@ (define-public ruby-redcloth
          ;; existing gemspec.
          (replace 'build
           (lambda _
-            (zero? (system* "gem" "build" "redcloth.gemspec"))))
+            (zero? (system* "gem" "build" "redcloth.gemspec")))))))
-         ;; Make sure that the "redcloth" executable finds required Ruby
-         ;; libraries.
-         (add-after 'install 'wrap-bin-redcloth
-          (lambda* (#:key outputs #:allow-other-keys)
-            (wrap-program (string-append (assoc-ref outputs "out")
-                                         "/bin/redcloth")
-              `("GEM_PATH" ":" prefix (,(string-append
-                                         (assoc-ref outputs "out")
-                                         "/lib/ruby/vendor_ruby"))))
-            #t)))))
     (native-inputs
      `(("bundler" ,bundler)
        ("ruby-diff-lcs" ,ruby-diff-lcs)
@@ -3710,13 +3700,7 @@ (define-public ruby-httpclient
                   (system* "ruby"
                            "-Ilib"
                            "test/runner.rb"))
-                 #t)))
+                 #t))))))
-         (add-after 'install 'wrap-bin-httpclient
-           (lambda* (#:key outputs #:allow-other-keys)
-             (wrap-program (string-append (assoc-ref outputs "out")
-                                          "/bin/httpclient")
-               `("GEM_PATH" ":" prefix (,(getenv "GEM_PATH"))))
-             #t)))))
     (native-inputs
      `(("ruby-rack" ,ruby-rack)))
     (synopsis