[ws-manager-mk2] Ensure prebuilds can start and stop

[Furisto]

Description

Note: This depends on #16471

Ensures that prebuilds can initialize successfully (before storage access was missing) and stopping successfully (by ensuring workspaces enter stopped phase once backup has been taken and deleting the prebuild pod so that workspace CR deletion can be performed)

Related Issue(s)

n.a.

How to test

• Create project in preview environment
• Start prebuild
• Prebuild should initialize and run successfully and enter stopped phase once completed. Afterwards the workspace CR should be deleted.

Release Notes

None

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

[WVerlaek]

/werft run with-preview=true with-wsman-mk2=true with-gce-vm=true

👍 started the job as gitpod-build-fo-mk2-prebuilds.3
(with .werft/ from main)

[WVerlaek]

@Furisto could you also enable and update/add controller tests for headless workspaces here?