[ws-manager-mk2] Add queue depth and work duration panels

[WVerlaek]

Description

Add workqueue depth and workqueue work duration panels to the mk2 dashboard:

Work duration metrics aren't scraped yet but get enabled here: https://github.com/gitpod-io/ops/pull/8444

Related Issue(s)

Part of #11416

How to test

View here: https://grafana.gitpod.io/d/ws-manager-mk2/gitpod-component-ws-manager-mk2?orgId=1&from=now-30d&to=now

Release Notes

NONE

Documentation

Build Options:

• /werft with-github-actions
  Experimental feature to run the build with GitHub Actions (and not in Werft).
• leeway-no-cache
  leeway-target=components:all
• /werft no-test
  Run Leeway with --dont-test

Publish Options

• /werft publish-to-npm
• /werft publish-to-jb-marketplace

Installer Options

• with-ee-license
• with-slow-database
• with-dedicated-emulation
• with-ws-manager-mk2
• workspace-feature-flags
  Add desired feature flags to the end of the line above, space separated

Preview Environment Options:

• /werft with-local-preview
  If enabled this will build install/preview
• /werft with-preview
• /werft with-large-vm
• /werft with-gce-vm
  If enabled this will create the environment on GCE infra
• /werft with-integration-tests=all
  Valid options are all, workspace, webapp, ide, jetbrains, vscode, ssh