tdg_dashboard: add REST API requests panels

Add "TDG REST API requests" section to TDG dashboard templates.
It consists of panels with following metrics:
- tdg_rest_exec_time_count
- tdg_rest_exec_time

Part of #134

CHANGELOG.md

@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - File connectors panels for TDG dashboard
 - GraphQL requests panels for TDG dashboard
 - IProto requests panels for TDG dashboard
+- REST API requests panels for TDG dashboard
 
 
 ## [1.1.0] - 2022-05-17

dashboard/influxdb_tdg_dashboard.libsonnet

@@ -178,4 +178,10 @@ dashboard.new(
     policy=variable.influxdb.policy,
     measurement=variable.influxdb.measurement,
   )
+).addPanels(
+  section.tdg_rest_api(
+    datasource=variable.datasource.influxdb,
+    policy=variable.influxdb.policy,
+    measurement=variable.influxdb.measurement,
+  )
 )