Remove InfluxDB data source Grafana plugin

Grafana has now native support for configuring Influxdb data sources.
Plugin has been defunct anyway since Grafana requires it to be signed.

Change-Id: I461f598bca6606f1d2939e385bb7befe2b792aa6

Author: cityofships

docker/grafana/Dockerfile.j2

@@ -30,7 +30,6 @@ COPY extend_start.sh /usr/local/bin/kolla_extend_start
 {% block grafana_plugins_install %}
 
 RUN grafana-cli plugins install gnocchixyz-gnocchi-datasource \
-    && grafana-cli plugins install grafana-influxdb-08-datasource \
     && grafana-cli plugins install monasca-datasource
 
 {% endblock %}

releasenotes/notes/remove-grafana-influxdb-plugin-a494f3dc217d3124.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Removes InlfuxDB datasource plugin from Grafana image as it is now natively
+    supported.