Tweaks wording in guide [skip ci]

The way it was written, it was not 100% clear if that was the name
to choose or the one to avoid.

Author: fxn

guides/source/autoloading_and_reloading_constants.md

@@ -411,7 +411,7 @@ However, if an engine supports Rails 6 or Rails 6.1 and does not control its par
 
 1. If `classic` mode would need a `require_dependency` call to ensure some constant is loaded at some point, write it. While `zeitwerk` would not need it, it won't hurt, will just work in `zeitwerk` mode too.
 
-2. `classic` mode underscores constant names ("User" -> "user.rb"), and `zeitwerk` mode camelizes file names ("user.rb" -> "User"). They coincide in most cases, but they don't if there are series of consecutive uppercase letters as in "HTMLParser". The easiest way to be compatible is to avoid such names: "HtmlParser".
+2. `classic` mode underscores constant names ("User" -> "user.rb"), and `zeitwerk` mode camelizes file names ("user.rb" -> "User"). They coincide in most cases, but they don't if there are series of consecutive uppercase letters as in "HTMLParser". The easiest way to be compatible is to avoid such names. In this case, better pick "HtmlParser".
 
 3. In `classic` mode, a file `app/model/concerns/foo.rb` is allowed to define both `Foo` and `Concerns::Foo`. In `zeitwerk` mode, there's only one option: it has to define `Foo`. In order to be compatible, define `Foo`.