doc: remove trailing whitespace

PR-URL: nodejs#24642
Reviewed-By: Refael Ackermann <[email protected]>
Reviewed-By: Franziska Hinkelmann <[email protected]>
Reviewed-By: Rich Trott <[email protected]>

Author: watilde

README.md

@@ -62,7 +62,7 @@ The open source license grants you the freedom to use Node.js. It does not
 guarantee commitments of other people's time. Please be respectful and manage
 your expectations.
 
-## Release Types 
+## Release Types
 
 * **Current**: Under active development. Code for the Current release is in the
   branch for its major version number (for example,