Resyncing Glossary file with v2.9 docs and resyncing versioned sidebars that were missing the glossary field.

Signed-off-by: Sunil Singh <sunil.singh@suse.com>

versioned_sidebars/version-2.9-sidebars.json

@@ -1322,6 +1322,7 @@
         "api/v3-rancher-api-guide"
       ]
     },
-    "contribute-to-rancher"
+    "contribute-to-rancher",
+    "glossary"
   ]
 }