[ws-manager-mk2] Refactor metric collection and add tests

[WVerlaek]

Description

• Refactor how metrics are recorded. Fixes some condition changes being ignored.
  • Instead of only checking for metric updates on a workspace's phase change, now keep track of a struct per workspace that contains which conditions have been recorded, and diff on each reconcile. This ensures we notice a condition change even when the phase doesn't change
• Add unit testing for metrics

Related Issue(s)

Part of #11416

How to test

cd components/ws-manager-mk2
go test ./...

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