[observability] add supervisor dashboard (#17031)

Author: mustard-mh

operations/observability/mixins/IDE/dashboards.libsonnet

@@ -13,6 +13,7 @@
     'gitpod-component-openvsx-proxy.json': (import 'dashboards/components/openvsx-proxy.json'),
     'gitpod-component-openvsx-mirror.json': (import 'dashboards/components/openvsx-mirror.json'),
     'gitpod-component-ssh-gateway.json': (import 'dashboards/components/ssh-gateway.json'),
+    'gitpod-component-supervisor.json': (import 'dashboards/components/supervisor.json'),
     'gitpod-component-jb.json': (import 'dashboards/components/jb.json'),
     'gitpod-component-browser-overview.json': (import 'dashboards/components/browser-overview.json'),
     'gitpod-component-code-browser.json': (import 'dashboards/components/code-browser.json'),