added text panel to visualizations (#24454)

docs/sources/panels/visualizations/text-panel.md

++++
+title = "Text panel"
+keywords = ["grafana", "text", "documentation", "panel"]
+type = "docs"
+aliases = ["/docs/grafana/latest/reference/alertlist/", "/docs/grafana/latest/features/panels/text/"]
+[menu.docs]
+name = "text-panel"
+parent = "visualizations"
+weight = 700
+draft = "true"
++++
+
+# Text panel
+
+The text panel lets you make information and description panels for your dashboards. 
+
+In **Mode**, select whether you want to use markdown or HTML to style your text, then enter content in the box below. Grafana includes a title and paragraph to help get you started, or you can paste content in from another editor.