[LG-499] Rake task copies phone info to new table

[jgsmith-usds]

Why:
We want to make sure all phone configurations are present in
the new table before we start reading data from the table.

How:
We use a rake task that processes users in batches to make
sure a phone configuration row exists for the user.

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CONTRIBUTING.md

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• When adding a new controller that requires the user to be fully
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  who might not have interacted with this column yet (such as users who have not
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[jgsmith-usds]

I'm open to other ideas for naming the task. It's a migration of data from one table to another, but this could also confuse folk looking for rails migrations.

[monfresh]

Assuming this is a one-time only task, I don't think the name matters a whole lot, but in the past, I've seen namespaces like adhoc used for one-off tasks.

What do you think about creating an issue to assign the running of this task to someone, and include the command to run?

Would there be a reason to keep this code around after the task is run? If not, another issue to remove the code from this PR after the task is run?

[stevegsa]

Do we need confirmation_sent_at?

[stevegsa]

is this line necessary?

[monfresh]

What do you think about naming this CopyPhonesToPhoneConfigurations for more accuracy?

[monfresh]

What do you think about naming this call for consistency with our other service objects?

[monfresh]

Should we use create_phone_configuration! to catch any validation errors?

[stevegsa]

LGTM