devworkspace-generator should not use resources published by plugin registry

[svor]

Is your task related to a problem? Please describe

devworkspace-generator uses resources published by plugin registry: https://github.com/devfile/devworkspace-generator/blob/main/src/main.ts#L60. It happens when ediotrPath or editorContent is not provided as a parameter.

Since che-plugin registry is going to be deprecated and all editors definitions were moved into che-operator, devworkspace generaor needs to be adapted to these changes.

Describe the solution you'd like

Use editors definitions from che-operator repo if editorPath or editorContent is not set

Describe alternatives you've considered

At least one of editorPath or editorContent parameter should be set when executing the generator

Additional context

No response