[MVP] Step 4 household info: Add alert for "yes" to "Is the land marketable?"

[vbellissimo]

Issue Description

Slack thread: https://dsva.slack.com/archives/C05MS96P6P2/p1704834631976679?thread_ts=1704484692.155699&cid=C05MS96P6P2

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Tasks

• [ ] If answering "yes" to "Is the additional land marketable?", add alert with the copy:

You'll need to submit an Income and Asset Statement in Support of Claim for Pension or Parents' Dependency and Indemnity Compensation (VA Form 21P-0969). Link this parentheses to: https://www.vba.va.gov/pubs/forms/VBA-21P-0969-ARE.pdf

We'll ask you to upload this form at the end of this application. Or you can email it to us.

Get VA form 21P-0969 to download. Link this sentence to: https://www.vba.va.gov/pubs/forms/VBA-21P-0969-ARE.pdf

Acceptance Criteria

[vbellissimo]

I saw this merged onto staging and verified the new alert is there. Thank you!