outpost/ldap: add sAMAccountName on groups for compatibility

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

internal/outpost/ldap/instance_search.go

@@ -182,6 +182,10 @@ func (pi *ProviderInstance) GroupEntry(g LDAPGroup) *ldap.Entry {
 			Name:   "uid",
 			Values: []string{g.uid},
 		},
+		{
+			Name:   "sAMAccountName",
+			Values: []string{g.cn},
+		},
 		{
 			Name:   "gidNumber",
 			Values: []string{g.gidNumber},