Migrate che projects to 'eclipse-che' organization

[nickboldt]

Is your task related to a problem? Please describe.

Followup to #18995. Rate limiting in GH actions is now causing releases to take significantly longer. che-theia release this week was queued for >5hrs before the 25 min build could run.

Projects to migrate:

• https://github.com/eclipse-che/che-machine-exec - Migrate che-operator and che-machine-exec to 'eclipse-che' organization #18995
• https://github.com/eclipse-che/che-operator - Migrate che-operator and che-machine-exec to 'eclipse-che' organization #18995
• https://github.com/eclipse/che-theia Migrate Che-Theia to eclipse-che GitHub organization #19391
• https://github.com/eclipse/che-devfile-registry - Migrate che-devfile-registry to the eclipse-che organization #19388
• https://github.com/eclipse/che-plugin-registry - Migrate the che-plugin-registry to the eclipse-che organization #19387
• https://github.com/eclipse/che-parent - Migrate maven projects involved in building Che server to new eclipse-che org  #19754
• https://github.com/eclipse/che (server) - Migrate maven projects involved in building Che server to new eclipse-che org  #19754
• https://github.com/eclipse/che-dashboard Migrate che workspace client and che dashboard to eclipse-che org #19614
• https://github.com/eclipse/che-workspace-client Migrate che workspace client and che dashboard to eclipse-che org #19614

Projects we don't have to migrate:

• https://github.com/che-incubator/chectl
• https://github.com/che-incubator/devworkspace-che-operator
• https://github.com/devfile/devworkspace-operator

Projects we could migrate (but won't bother for now):

• che-parent
• che-dev
• che-lib

Describe the solution you'd like

In order to migrate che-* projects to new organization we should consider:

• Sync all release scripts
• Install Openshift CI github application in the new organization and related webhooks
• Make sure all tests will work in the new organization
• impacts on downstream syncs/jobs - https://gitlab.cee.redhat.com/codeready-workspaces/crw-jenkins

Describe alternatives you've considered

Additional context

[nickboldt]

Che parent, dev, and lib were not migrated as per #19754 -> https://bugs.eclipse.org/bugs/show_bug.cgi?id=571958

But since they never get built anyway, I'm resolving this issue.

[benoitf]

@nickboldt should we move https://github.com/eclipse/che-release as well ?

[nickboldt]

We should! But I missed your comment here because firehose of GH emails :)

I've opened https://bugs.eclipse.org/bugs/show_bug.cgi?id=574569 to move che-release as @mkuznyetsov realized today that he's being throttled there too.

[nickboldt]

bug resolved. PR merged eclipse-che/che-release#38