audit: match #{prefix}/libexec and prefix+'libexec'

These were being picked up as just "#{prefix}/lib" and prefix+'lib' due
to the eagerness of the regex. Reordering "lib" and "libexec" will take
care of it; I couldn't think of a more clever solution.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Library/Homebrew/cmd/audit.rb

@@ -50,7 +50,7 @@ def audit_formula_text name, text
   end
 
   # Prefer formula path shortcuts in Pathname+
-  if text =~ %r{\(\s*(prefix\s*\+\s*(['"])(bin|include|lib|libexec|sbin|share))}
+  if text =~ %r{\(\s*(prefix\s*\+\s*(['"])(bin|include|libexec|lib|sbin|share))}
     problems << " * \"(#{$1}...#{$2})\" should be \"(#{$3}+...)\""
   end
 
@@ -59,7 +59,7 @@ def audit_formula_text name, text
   end
 
   # Prefer formula path shortcuts in strings
-  if text =~ %r[(\#\{prefix\}/(bin|include|lib|libexec|sbin|share))]
+  if text =~ %r[(\#\{prefix\}/(bin|include|libexec|lib|sbin|share))]
     problems << " * \"#{$1}\" should be \"\#{#{$2}}\""
   end