Update month data fields to be strings

[futa-ikeda]

• Ticket: [No ticket]
• Feature flag: n/a

Purpose

• Update institution-user date fields to be strings to avoid a bug where month data would be shown incorrectly

Summary of Changes

• Don't use date transform for InstitutionUser model's monthLastLogin, monthLastActive, and accountCreationDate
  • Use of this transform was causing problems with the display of these fields as the API would return account_creation_date: "2024-10", but the date transform would convert that to 9/2024 depending on timezone
    (e.g. new Date('2024-10') // Mon Sep 30 2024 20:00:00 GMT-0400 (Eastern Daylight Time) {})

Screenshot(s)

• Prevents this issue (Note the date in the API response and the date displayed in the table):
  

Side Effects

QA Notes

• Great find!