In UIM 9.10 we had option to delete servers from Inventory node. In new 20.3 OC, It does not seem to be we have an option. Please check out and do let me know how can we get around this.
Release : 20.3
Component : Operator Console
Delete device feature will be available at the UIM 20.3 Service Pack 1, that it is expected to be released in November 2020.
As a workaround, you can test in your LAB:
https://knowledge.broadcom.com/external/article?articleId=201112