Doc: Add Run Migration Script instruction to README.md when new version is added to the repo.

[mtreacy002]

Description

As a contributor, I need to add instruction on how to run migration script when a new version of migration script is added to the repo, so that the contributors can update their db schemas when there is a schema update.

Acceptance Criteria

Update [Required]

• [ ] add a section on Run migration script to README.md for when a new migration script is added to the repo.

Definition of Done

• [ ] All of the required items are completed.
• [ ] Approval by 1 mentor.

Estimation

1 hr

[vj-codes]

@mtreacy002 hey how this different from issue #996 and PR #1038

[mtreacy002]

🤔 , @vj-codes , I think #996 is addressing what contributors should do after they make changes to the db aka they need to create a new migration script within the PR where the db models are being changed. Whereas this issue is addressing what other contributors should do as an impact of a new migration script being merged to the repo when they pull the latest update from the repo. I will modify this issue title and description so to reflect this. Thanks for making me aware of the other issue and pr 😉 . cc @isabelcosta and @epicadk