Clarify Bootstrap versions in readme

Author: mdo

README.md

@@ -8,7 +8,7 @@
 
 ## About
 
-`bootstrap-npm-starter` is a GitHub template repository for creating new Bootstrap-powered npm projects, maintained by Bootstrap co-author @mdo. You can also use it as your own Bootstrap prototyping sandbox. It's built with Bootstrap v4.5.0 with plans to update for v5.
+`bootstrap-npm-starter` is a GitHub template repository for creating new Bootstrap-powered npm projects, maintained by Bootstrap co-author @mdo. You can also use it as your own Bootstrap prototyping sandbox. It's built with Bootstrap v4 with plans to update for v5.
 
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