wifi/wwan test fail due to access io.netplan.Netplan fail

[Rick Wu]

[Summary]
wifi/wwan test fail due to access io.netplan.Netplan fail. However, if we apply netplan manually, then it will be no any issue. And wifi can be applied and worked.

[Steps to reproduce]
1. Run job "wireless/wireless_connection_open_ac_np.*"

[Expected result]
WiFi connection test should be pass.

[Actual result]
WiFi connection test fail due to access io.netplan.Netplan fail.

## Apply the test configuration
+ netplan --debug apply
Call failed: Failed to execute program io.netplan.Netplan: Permission denied
ERROR: failed netplan apply call

[Failure rate]
100%

[Additional information]
image: iot-zhongyi-classic-server-2004-classic-x06-20220620-94
kernel: 5.4.0-1015-imx #15
snap: checkbox20 1.28 rev 976

[Rick Wu (rickwu4444)]

I found that if adding "sudo" in front of "netplan --debug apply" then this issue won't happen.

https://git.launchpad.net/plainbox-provider-checkbox/tree/bin/wifi_client_test_netplan.py#n184

[Maksim Beliaev (beliaev-maksim)]

Bug was migrated to GitHub: https://github.com/canonical/checkbox/issues/234.
Bug is no more monitored here.