Restore stdio passthrough behavior

[oliversalzburg]

Platforms affected

iOS

What does this PR do?

It restores the stdio setting that was previously applied through the spawn.js shell execution utility.

In the current setting, previously visible console output would likely be hidden from the user.

What testing has been done on this change?

None

[codecov-io]

Codecov Report

Merging #483 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master     #483   +/-   ##
=======================================
  Coverage   75.66%   75.66%           
=======================================
  Files          11       11           
  Lines        1796     1796           
=======================================
  Hits         1359     1359           
  Misses        437      437

Impacted Files	Coverage Δ
bin/templates/scripts/cordova/lib/build.js	57.71% <0%> (ø)	⬆️
bin/templates/scripts/cordova/lib/run.js	23.36% <0%> (ø)	⬆️

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[brodycj]

Approved on my part, would like another quick review since I am not so familiar with this behavior.