Fixed internet connectivity detection

testing internet connectivity through connection test to 1.1.1.1:53
instead of www.google.com:80

In case internet is actually not present, previous test would fail (indicating connectio OK)
after receiving captive portal response from HTTP due to DNSmasq.

New test would not be spoofed and is thus more reliable
1 job for master in 307 minutes and 44 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #622286
build-pibox-image

05:07:44