doctor: handle non-extent methods passed as arguments

Library/Homebrew/cmd/doctor.rb

@@ -1207,7 +1207,13 @@ module Homebrew
 
     first_warning = true
     methods.each do |method|
-      out = checks.send(method)
+      begin
+        out = checks.send(method)
+      rescue NoMethodError
+        Homebrew.failed = true
+        puts "No check available by the name: #{method}"
+        next
+      end
       unless out.nil? or out.empty?
         if first_warning
           puts <<-EOS.undent