[theia-devworkspace handler] store projects section when generating templates

[benoitf]

Is your enhancement related to a problem? Please describe

For now the projects section is empty
It should generate the projects section in the devfile.yaml

Describe the solution you'd like

Option to include or not the projects section
When using the CLI it should include the projects section while when running inside dashboard it shouldn't

projects:
  - name: scala-sbt
    source:
      location: 'https://github.com/che-samples/scala-sbt'
      type: git
      branch: devfile2

if we add flag like npx devworkspace-handler ...... --project.${name}={{DEVFILE_REGISTRY_URL}}/${name}.zip

it should be like

projects:
  - name: scala-sbt
    source:
      location: '{{DEVFILE_REGISTRY_URL}}/resources/v2/scala-sbt.zip'
      type: zip

Describe alternatives you've considered

No response

Additional context

No response