doc: add branding to style guide

PR-URL: #23967
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: Trivikram Kamat <[email protected]>
Reviewed-By: Matheus Marchini <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Franziska Hinkelmann <[email protected]>
Reviewed-By: Vse Mozhet Byt <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>

Author: Trott

doc/STYLE_GUIDE.md

@@ -65,6 +65,8 @@
   <!--lint disable prohibited-strings remark-lint-->
   * NOT OK: Javascript, Google's v8
   <!-- lint enable prohibited-strings remark-lint-->
+* Use _Node.js_ and not _Node_, _NodeJS_, or similar variants.
+  * When referring to the executable, _`node`_ is acceptable.
 
 See also API documentation structure overview in [doctools README][].