Docs: fix time series table (#23400)

Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com>

docs/sources/guides/timeseries.md

@@ -96,15 +96,15 @@ Here are some of the TSDBs supported by Grafana:
 - [InfluxDB](https://www.influxdata.com/products/influxdb-overview/)
 - [Prometheus](https://prometheus.io/)
 
-```
-weather,location=us-midwest temperature=82 1465839830100400200
+    ```
+    weather,location=us-midwest temperature=82 1465839830100400200
       |    -------------------- --------------  |
       |             |             |             |
       |             |             |             |
-+-----------+--------+-+---------+-+---------+
-|measurement|,tag_set| |field_set| |timestamp|
-+-----------+--------+-+---------+-+---------+
-```
+    +-----------+--------+-+---------+-+---------+
+    |measurement|,tag_set| |field_set| |timestamp|
+    +-----------+--------+-+---------+-+---------+
+    ```
 
 ### Collecting time series data