fix(helm): do not deploy screenshot to cluster (just dashboard) (#3063)

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Signed-off-by: genofire <geno+dev@fireorbit.de>
Co-authored-by: kegsay <kegan@matrix.org>

helm/dendrite/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v2
 name: dendrite
-version: "0.12.2"
+version: "0.12.3"
 appVersion: "0.12.0"
 description: Dendrite Matrix Homeserver
 type: application

helm/dendrite/templates/configmap_grafana_dashboards.yaml

@@ -1,5 +1,5 @@
 {{- if .Values.grafana.dashboards.enabled }}
-{{- range $path, $bytes := .Files.Glob "grafana_dashboards/*" }}
+{{- range $path, $bytes := .Files.Glob "grafana_dashboards/*.json" }}
 ---
 apiVersion: v1
 kind: ConfigMap