Mono repo -> Master (#22553)

Combines the following repositories into one:

https://github.com/mattermost/mattermost-server
https://github.com/mattermost/mattermost-webapp
https://github.com/mattermost/focalboard
https://github.com/mattermost/mattermost-plugin-playbooks

server/build/docker/grafana/provisioning/dashboards/mattermost.yaml

@@ -0,0 +1,14 @@
+apiVersion: 1
+
+providers:
+  - name: 'mattermost'
+    orgId: 1
+    folder: 'mattermost'
+    type: file
+    disableDeletion: true
+    updateIntervalSeconds: 300
+    allowUiUpdates: true
+    options:
+      # <string, required> path to dashboard files on disk. Required when using the 'file' type
+      path: /var/lib/grafana/dashboards
+      foldersFromFilesStructure: true

server/build/docker/grafana/provisioning/datasources/prometheus.yml

@@ -0,0 +1,11 @@
+apiVersion: 1
+
+datasources:
+  - name: Prometheus
+    type: 'prometheus'
+    access: 'proxy'
+    orgId: 1
+    url: 'http://prometheus:9090'
+    isDefault: true
+    version: 1
+    editable: false