BD-3572 Move SMS note to a Consideratinos section in User Import

[rachel-feinberg]

Why are you making this change? (required)

I moved the SMS note to a new section (Considerations) on the User Import page. A PM requested that the note be added to that page among others, so I don't want to remove it.

Related PRs, issues, or features (optional)

BD-3572

Feature release date (optional)

• N/A

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