Error: Unable to publish when Delegation Enable

[asasar]

I am following Self hosting the portal documentation.

Bug description

At enable the identity delegation and trying to publish the site with the command

npm run publish

Publishing {"message":"Publishing website..."}
Publishing {"message":"Publishing page APIs: Changelog - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page APIs: List - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Errors: 500 Internal error - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page APIs: Details - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Change password - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Confirm password - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Errors: 404 Page not found - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Sign in - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Sign up - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Products: Details - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Sign up with OAuth - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Products: List - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Reset password - Microsoft Azure API Management - developer portal..."}
Publishing {"message":"Publishing page Home - Microsoft Azure API Management - developer portal..."}
Error: Unable to complete publishing. Error: Unable to complete pages publishing. Error: Unable to publish page "Sign in":
0 t PagePublisher. (C:\pathToFiles\dist\publisher\index.js :44939:23)
at Generator.throw ()
at rejected (C:\pathToFiles\dist\publisher\index.js:44793:65)
at processTicksAndRejections (internal/process/task_queues.js:97:5)
at PagePublisher. (C:\pathToFiles\dist\publisher\index.js :44974:23)
at Generator.throw ()
at rejected (C:\pathToFiles\dist\publisher\index.js:44793:65)
at processTicksAndRejections (internal/process/task_queues.js:97:5)
at SitePublisher. (C:\pathToFiles\dist\publisher\index.js:63433:23)
at Generator.throw ()
at rejected (C:\pathToFiles\dist\publisher\index.js:63399:65)

Reproduction steps

1. Go to Developer portal -> Delegation
2. Check Delegate sign-in & sign-up
3. Enter Delegation endpoint URL -> https://myIdentityServer4.azurewebsites.net/Account/Delegation
4. Save
5. npm run publish

Is your portal managed or self-hosted?

Self-hosted

Release tag or commit SHA (if using self-hosted version)

[e.g., release 2.0.0, commit c45da9778b70d369aba60fa2e63c191efe2b548f]

[tOmoness]

Related to #785 for sure.

[ygrik]

Please add following parameter in config.publish.json
"backendUrl": "https://.developer.azure-api.net"

Close with #834