Duplicate object key on identity groups when service account name is the same

[brettcurtis]

╷
│ Error: Duplicate object key
│ 
│   on locals.tf line 71, in locals:
│   51:   owners = { for owner in flatten([
│   52:     # This will iterate over the identity_groups map and return a list of maps based of the values of the owners
│   53:     # that includes the group key.
│   54:     for identity_group_key, group in var.identity_groups : [
│   55:       for owner in group.owners : {
│   56:         group = identity_group_key
│   57:         owner = owner
│   58:         # Split Function
│   59:         # https://developer.hashicorp.com/terraform/language/functions/split
│   60:         # This will split the owner string into a list of strings based on the @ symbol.
│   61:         # We do this because the owner string is an email address and we want to use the
│   62:         # the group plus the first part of the email address as resource name key.
│   63:         owner_split = split("@", owner)
│   64:       }
│   65:     ]
│   66:   ]) : "${owner.group}-${owner.owner_split[0]}" => owner }
│     ├────────────────
│     │ owner.group is "backstage"
│     │ owner.owner_split[0] is "plt-backstage-github"
│ 
│ Two different items produced the key "backstage-plt-backstage-github" in this 'for' expression. If duplicates are expected, use the ellipsis (...) after the value expression
│ to enable grouping by key.
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