fix resource owner display on backup list (#1580)

## Type of change

- [x] 🐛 Bugfix

## Issue(s)

* #1506

## Test Plan

- [x] ⚡ Unit test

src/pkg/selectors/selectors.go

@@ -296,8 +296,8 @@ func resourcesShortFormat(m map[string][]string) string {
 }
 
 // Transforms the slice to a single map.
-// Keys are each map's scopeKeyResource value.
+// Keys are each service's rootCat value.
-// Values are the set of all scopeKeyDataTypes for a given resource.
+// Values are the set of all scopeKeyDataTypes for the resource.
 func toResourceTypeMap[T scopeT](s []scope) map[string][]string {
 	if len(s) == 0 {
 		return nil
@@ -314,7 +314,9 @@ func toResourceTypeMap[T scopeT](s []scope) map[string][]string {
 			k = All
 		}
 
-		r[k] = addToSet(r[k], split(sc[scopeKeyDataType].Target))
+		for _, sk := range split(k) {
+			r[sk] = addToSet(r[sk], split(sc[scopeKeyDataType].Target))
+		}
 	}
 
 	return r

src/pkg/selectors/selectors_test.go

@@ -106,6 +106,21 @@ func (suite *SelectorSuite) TestToResourceTypeMap() {
 				"smarf": {unknownCatStub.String()},
 			},
 		},
+		{
+			name: "multiple resources",
+			input: []scope{
+				scope(stubScope("")),
+				{
+					rootCatStub.String(): filterize(scopeConfig{}, join("smarf", "fnords")),
+					scopeKeyDataType:     filterize(scopeConfig{}, unknownCatStub.String()),
+				},
+			},
+			expect: map[string][]string{
+				"All":    {rootCatStub.String()},
+				"smarf":  {unknownCatStub.String()},
+				"fnords": {unknownCatStub.String()},
+			},
+		},
 		{
 			name: "disjoint types",
 			input: []scope{