clojure-align-separator: shorten docstring to satisfy test-bytecomp

In toplevel form:
clojure-mode.el:1135:1: Error: custom-declare-variable `clojure-align-separator' docstring wider than 80 characters
make: *** [Makefile:41: clojure-mode.elc-test] Error 1

Author: rlbdv

Diff for: clojure-mode.el

@@ -1133,7 +1133,7 @@ will align the values like this:
 (defconst clojure--align-separator-newline-regexp "^ *$")
 
 (defcustom clojure-align-separator clojure--align-separator-newline-regexp
-  "The separator that will be passed to `align-region' when performing vertical alignment."
+  "Separator passed to `align-region' when performing vertical alignment."
   :package-version '(clojure-mode . "5.10")
   :type `(choice (const :tag "Make blank lines prevent vertical alignment from happening."
                         ,clojure--align-separator-newline-regexp)