[Bug] Change the timeout to 10 seconds

[hwchiu]

We will meet the random testing fail in the travis CI environment.
The message is context deadline exceeded and We thinks it's caused by the client didn't get the response from the grpc Server in a timeout value.
The current value is one second and we try to change to ten seconds to validate our guess.

[codecov-io]

Codecov Report

Merging #199 into develop will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff            @@
##           develop     #199   +/-   ##
========================================
  Coverage    78.71%   78.71%           
========================================
  Files           45       45           
  Lines         2218     2218           
========================================
  Hits          1746     1746           
  Misses         365      365           
  Partials       107      107

Impacted Files	Coverage Δ
src/networkcontroller/network_controller.go	82.27% <100%> (ø)	⬆️

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