docs(reference): removed link to non existant text panel page, fixes #2632

docs/mkdocs.yml

@@ -49,7 +49,6 @@ pages:
 - ['reference/graph.md', 'Reference', 'Graph Panel']
 - ['reference/singlestat.md', 'Reference', 'Singlestat Panel']
 - ['reference/dashlist.md', 'Reference', 'Dashboard List Panel']
-- ['reference/text.md', 'Reference', 'Text Panel']
 - ['reference/sharing.md', 'Reference', 'Sharing']
 - ['reference/annotations.md', 'Reference', 'Annotations']
 - ['reference/timerange.md', 'Reference', 'Time Range Controls']