fix: pass --env.verbose to webpack compiler

[Fatme]

copy-webpack plugin prints its info messages on stderr by default. This led to the problem that these messages are shown in errors tab in Sidekick.
When { verbose: false } is provided as option to copy-webpack plugin, it doesn't print any information. So when tns run android is executed, no messages will be shown from copy-webpack plugin and thus no errors will be shown from Sidekick.

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What is the current behavior?

What is the new behavior?

Fixes/Implements/Closes #[Issue Number].