Added Network - DNS Private Resolver label (#9112)

tools/github/data/common-labels.csv

@@ -169,6 +169,7 @@ Network - Bastion,,e99695
 Network - CDN,,e99695
 Network - DDoS Protection,,e99695
 Network - DNS,,e99695
+Network - DNS Private Resolver,,e99695
 Network - ExpressRoute,,e99695
 Network - Firewall,,e99695
 Network - Front Door,Service: Azure Front Door,e99695