Docs: Fix intro to timeseries URL (#25530)

* Docs: Fix intro to timeseries URL

* Update docs/sources/developers/plugins/data-frames.md

Co-authored-by: Marcus Olsson <accounts+github@marcus.se.net>

Co-authored-by: Marcus Olsson <accounts+github@marcus.se.net>

docs/sources/developers/plugins/data-frames.md

@@ -73,7 +73,7 @@ A data transformation is any function that accepts a data frame as input, and re
 
 A data frame with at least one time field is considered a _time series_.
 
-For more information on time series, refer to our [Introduction to time series](https://grafana.com/docs/grafana/latest/guides/timeseries/).
+For more information on time series, refer to our [Introduction to time series]({{< relref "../../getting-started/timeseries.md" >}}).
 
 ### Wide format