[css-text] update test coverage

Author: frivoal

css-text-3/Overview.bs

@@ -1628,6 +1628,9 @@ Order of Operations</h4>
           white-space/pre-float-001.html
           white-space/pre-wrap-float-001.html
           white-space/trailing-space-before-br-001.html
+          white-space/trailing-ogham-001.html
+          white-space/trailing-ogham-002.html
+          white-space/trailing-ogham-003.html
         </wpt>
         <wpt pathprefix="/css/CSS2/text/">
           white-space-collapsing-003.xht

css-text-3/test-coverage.html

@@ -154,7 +154,6 @@ <h4 id="phase-ii-trimming-and-positioning">4.1.3 <a href="https://drafts.csswg.o
 <ul>
 	<li>test for <a href=https://github.com/w3c/csswg-drafts/issues/4422>https://github.com/w3c/csswg-drafts/issues/4422</a>
 	<li>See [UAX9] for rules on how U+0009 tabulation interacts with bidi.
-	<li>Trailing OGHAM spaces <a href=https://github.com/w3c/csswg-drafts/issues/4893>https://github.com/w3c/csswg-drafts/issues/4893</a>
 </ul>
 
 <h4 id="segment-break-transformation-rules">4.1.2 <a href="https://drafts.csswg.org/css-text-3/#line-break-transform">Segment Break Transformation Rules</a></h4>