[css-text] Typo in Example 1 (line-breaking to letter-spacing)

Author: kojiishi

css-text/Overview.bs

@@ -222,7 +222,7 @@ Characters and Letters</h4>
     <p>In other scripts such as Thai or Lao,
     even though for line-breaking the <i>typographic character</i>
     matches Unicode’s default <i>grapheme clusters</i>,
-    for line-breaking the relevant unit
+    for letter-spacing the relevant unit
     is <em>less</em> than a [[!UAX29]] <i>grapheme cluster</i>,
     and may require decomposition or other substitutions
     before spacing can be inserted.