Display internal flag on network inspect

Also adds internal network tests for bridge network

Signed-off-by: Chun Chen <ramichen@tencent.com>
Upstream-commit: 355a190423
Component: cli

components/cli/docs/reference/commandline/network_inspect.md

@@ -50,6 +50,7 @@ $ sudo docker network inspect bridge
                 }
             ]
         },
+        "Internal": false,
         "Containers": {
             "bda12f8922785d1f160be70736f26c1e331ab8aaf8ed8d56728508f2e2fd4727": {
                 "Name": "container2",

components/cli/man/docker-network-inspect.1.md

@@ -45,6 +45,7 @@ $ sudo docker network inspect bridge
                 }
             ]
         },
+        "Internal": false,
         "Containers": {
             "bda12f8922785d1f160be70736f26c1e331ab8aaf8ed8d56728508f2e2fd4727": {
                 "Name": "container2",