correct the extra attribute to be XHTML valid

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@19955 20353a03-c40f-0410-a6d1-a30d3c3de9de

bt5/erp5_forge/SkinTemplateItem/portal_skins/erp5_forge/Bug_view/follow_up.xml

@@ -240,7 +240,7 @@
                 </item>
                 <item>
                     <key> <string>extra</string> </key>
-                    <value> <string>readonly</string> </value>
+                    <value> <string>readonly="readonly"</string> </value>
                 </item>
                 <item>
                     <key> <string>height</string> </key>

bt5/erp5_forge/bt/revision

-214
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+215
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