Cannot install any plugin from Plugins view

[svor]

Describe the bug

It is not possible to install any plug-in from PLUGINS view in the workspace. The error message is:

Unable to install plugin 'broadcommfd/cobol-language-support/latest'. Request addPlugin failed unexpectedly without providing any details.

Che version

• latest
• nightly
• other: please specify

Steps to reproduce

1. Create a workpsace
2. Open Plugins view
3. Try to install a plugin

Expected behavior

The plug-in should be installed

Runtime

• kubernetes (include output of kubectl version)
• Openshift (include output of oc version)
• minikube (include output of minikube version and kubectl version)
• minishift (include output of minishift version and oc version)
• docker-desktop + K8S (include output of docker version and kubectl version)
• other: (please specify)

Screenshots

Installation method

• chectl (chectl/0.0.20210416-next.12aa7b6 linux-x64 node-v12.22.1)
  • provide a full command that was used to deploy Eclipse Che (including the output)
  • provide an output of chectl version command
• OperatorHub
• I don't know

Environment

• my computer
  • Windows
  • Linux
  • macOS
• Cloud
  • Amazon
  • Azure
  • GCE
  • other (please specify)
• Dev Sandbox (workspaces.openshift.com)
• other: please specify