[css-fonts-4] Add font feature technology keywords, see w3c#6372

Author: svgeesus

css-fonts-4/Overview.bs

@@ -2023,9 +2023,14 @@ The <dfn id="at-font-face-rule">''@font-face''</dfn> rule</h3>
 
     <pre class="prod"><dfn id="font-format-values">&lt;font-format&gt;</dfn> = [<<string>> | woff | truetype | opentype | woff2 | embedded-opentype | collection | svg]</pre>
 
-    <pre class="prod"><dfn id="font-technology-values">&lt;font-technology&gt;</dfn> = [features | variations | color(<<color-font-technology>>) | palettes]</pre>
+    <pre class="prod"><dfn id="font-technology-values">&lt;font-technology&gt;</dfn>
+		= [features(<<font-feature-technology>>) | variations | color(<<color-font-technology>>) | palettes]</pre>
 
-    <pre class="prod"><dfn id="color-font-technology-values">&lt;color-font-technology&gt;</dfn> = [COLRv0 | COLRv1 | SVG | sbix | CBDT ]</pre>
+	<pre class="prod"><dfn id="font-feature-technology-values">&lt;font-feature-technology&gt;</dfn>
+		= [opentype | aat | graphite]</pre>
+
+    <pre class="prod"><dfn id="color-font-technology-values">&lt;color-font-technology&gt;</dfn>
+		= [COLRv0 | COLRv1 | SVG | sbix | CBDT ]</pre>
 
     If a component value is parsed correctly
 	and is of a format and font technology that the UA supports,
@@ -7184,6 +7189,7 @@ Changes
 <!-- new ones at the top -->
 
 <ul>
+	<li>Added font feature technology keywords opentype, aat, and graphite</li>
 	<!-- to 9 June 2021 -->
 	<li>Removed scary wording about variable fonts being new and experimental</li>
 	<li>Reference to CSS Fonts 3 in introduction is informative</li>