feat: add iCloudContainerEnvironment build option

[jzgoda]

PR Checklist

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What is the current behavior?

Enterprise applications that use iCloud fail to build in 5.x.
(This was not an issue in prior versions.)

The error message is:

error: exportArchive: exportOptionsPlist error for key 'iCloudContainerEnvironment': expected one of {Development, Production}, but no value was provided

What is the new behavior?

Allow the user to pass a new --i-cloud-container-environment option (while doing a --for-device build), that accepts an environment string.

Fixes/Implements/Closes #4374.

[Fatme]

test cli-smoke

[Fatme]

test cli-smoke

[Fatme]

Hey @jzgoda,

Thank you very much for the contribution!

We think it'll be great to support merging of ExportOptions.plist from App_Resources and from plugins as described here.

We'll more than glad to help you, in case you're interested in implementing this feature.

[Fatme]

@jzgoda,

I forgot to mention that if this is your first contribution to NativeScript, you are eligible for our NativeScript First-Time Contribution program. More info can be found here

[jzgoda]

Thanks for merging, @Fatme!

I'll look into implementing #4528.