[css-fonts-4] remove message about incomplete porting from fonts 3

Author: svgeesus

css-fonts-4/Overview.bs

@@ -37,10 +37,7 @@ rules defined in CSS3 Fonts.
 Issue: Please note that OpenType/TrueType variable font support
 is still in initial stages of specification and implementation. Please
 comment on any bugs in this spec at <a href="https://github.com/w3c/csswg-drafts/issues">
-https://github.com/w3c/csswg-drafts/issues</a>. Also, please note that this
-spec is incomplete and only includes some of the text from <a href="https://www.w3.org/TR/css-fonts-3/">
-https://www.w3.org/TR/css-fonts-3/</a>.
-
+https://github.com/w3c/csswg-drafts/issues</a>.
 
 
 <h2 id="basic-font-props">