Avoid displaying new lines inside note paragraphs

Commit 65a2977c added a `pre-wrap` style for white spaces on `.note`
paragraphs. However, this is first inconsistent as other notes like
warnings don't have this style applied. Furthermore, it seems to be
unneeded for mobile devices.

Also revert changes made in #18147 since they aren't needed anymore.

Cross-refs #18138.

[ci skip]

guides/assets/stylesheets/main.css

@@ -34,7 +34,7 @@ pre, code {
   overflow: auto;
   color: #222;
 }
-pre,tt,code,.note>p {
+pre, tt, code {
  white-space: pre-wrap;       /* css-3 */
  white-space: -moz-pre-wrap !important;  /* Mozilla, since 1999 */
  white-space: -pre-wrap;      /* Opera 4-6 */

guides/source/active_record_querying.md

@@ -1384,7 +1384,8 @@ WHERE people.name = 'John'
 LIMIT 1
 ```
 
-NOTE: Remember that, if `find_by` returns more than one registry, it will take just the first and ignore the others. Note the `LIMIT 1` statement above.
+NOTE: Remember that, if `find_by` returns more than one registry, it will take
+just the first and ignore the others. Note the `LIMIT 1` statement above.
 
 Find or Build a New Object
 --------------------------

guides/source/security.md

@@ -249,7 +249,14 @@ protect_from_forgery with: :exception
 
 This will automatically include a security token in all forms and Ajax requests generated by Rails. If the security token doesn't match what was expected, an exception will be thrown.
 
-NOTE: By default, Rails includes jQuery and an [unobtrusive scripting adapter for jQuery](https://github.com/rails/jquery-ujs), which adds a header called `X-CSRF-Token` on every non-GET Ajax call made by jQuery with the security token. Without this header, non-GET Ajax requests won't be accepted by Rails. When using another library to make Ajax calls, it is necessary to add the security token as a default header for Ajax calls in your library. To get the token, have a look at `<meta name='csrf-token' content='THE-TOKEN'>` tag printed by `<%= csrf_meta_tags %>` in your application view.
+NOTE: By default, Rails includes jQuery and an [unobtrusive scripting adapter for
+jQuery](https://github.com/rails/jquery-ujs), which adds a header called
+`X-CSRF-Token` on every non-GET Ajax call made by jQuery with the security token.
+Without this header, non-GET Ajax requests won't be accepted by Rails. When using
+another library to make Ajax calls, it is necessary to add the security token as
+a default header for Ajax calls in your library. To get the token, have a look at
+`<meta name='csrf-token' content='THE-TOKEN'>` tag printed by
+`<%= csrf_meta_tags %>` in your application view.
 
 It is common to use persistent cookies to store user information, with `cookies.permanent` for example. In this case, the cookies will not be cleared and the out of the box CSRF protection will not be effective. If you are using a different cookie store than the session for this information, you must handle what to do with it yourself: