We need to set two config values in the staging slot:
You can do that in the Portal by adding a New application setting.
Or in the CLI:
az webapp config appsettings set --slot staging --settings Rng__Range__Min=50 -g labs-appservice-cicd -n <dns-name>
az webapp config appsettings set --slot staging --settings Rng__Range__Min=500 -g labs-appservice-cicd -n <dns-name>
Compare the Configuration blade for the two slots and you should see that only the staging slot has those settings.
Test the app at the staging URL:
curl https://<dns-name>-staging.azurewebsites.net/rng
And if it looks good, swap the staging and production slots:
az webapp deployment slot swap --slot staging --target-slot production -g labs-appservice-cicd -n <dns-name>