Add note on teletype styling in custom CSS

Signed-off-by: Roger Sheen <[email protected]>

release-notes/index.dita

@@ -101,7 +101,9 @@
             generated by previous toolkit versions.
             <xref href="https://github.com/dita-ot/dita-ot/issues/4254" format="html" scope="external">#4254</xref>,
             <xref href="https://github.com/dita-ot/dita-ot/issues/4267" format="html" scope="external">#4267</xref>
-          </li>          
+            <note type="important">In publishing environments that do not use the default common CSS files, these styles
+              may need to be implemented in custom stylesheets.</note>
+          </li>
           <li id="4259">Test coverage has been improved to include unit tests for preprocessing, integration tests for
             subject schemes, and unit tests for cascading metadata in duplicate topicrefs.
             <xref href="https://github.com/dita-ot/dita-ot/issues/4259" format="html" scope="external">#4259</xref>,
@@ -193,7 +195,7 @@
             <xref href="https://github.com/dita-ot/dita-ot/issues/4187" format="html" scope="external">#4187</xref>,
             <xref href="https://github.com/dita-ot/dita-ot/issues/4240" format="html" scope="external">#4240</xref>,
             <xref href="https://github.com/dita-ot/dita-ot/issues/4248" format="html" scope="external">#4248</xref>
-          </li>          
+          </li>
           <li>Several dependencies have been upgraded to include the latest utility versions and fix security issues in
             bundled libraries:
             <ul>