Dev: Add initial migration and Running migration instruction to README

[mtreacy002]

Description

Initiate migration script and add running migration script to README

Fixes #996

Type of Change:

• Code
• Documentation

Code/Quality Assurance Only

• This change requires a documentation update (software upgrade on readme file)
• New feature (non-breaking change which adds functionality pre-approved by mentors)

How Has This Been Tested?

1. On initiation of migration script/when contributors running migration script for the first time
   Confirmed that alembic version was added to the local db and the initial version was created under migrations > versions folder
   before running initial migration

after running initial migration

2. if contributor missed migration version updates

The local db will be updated one version at a time accordingly
from initial to second revision

from second to third revision

3. When you are making changes by adding attribute/s to an existing db model

4. When you are making changes by ALTERING EXISTING ATTRIBUTES inside an existing db model
   Example case: User table
   Changes:
   • renaming column name to full_name
   • change password_hash field length from 100 to unspecified

IMPORTANT Noticed that the auto-generated alembic script IS NOT CORRECT!!.
You MUST MODIFY the script to reflect the intended schema changes. Once you're done, you can run flask db upgrade

before alteration

After alteration (with data successfully preserved)

Checklist:

• My PR follows the style guidelines of this project
• I have performed a self-review of my own code or materials
• I have commented my code or provided relevant documentation, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• Any dependent changes have been merged
• Update Postman API at /docs folder
• Update Swagger documentation and the exported file at /docs folder
• Update requirements.txt

Code/Quality Assurance Only

• My changes generate no new warnings
• My PR currently breaks something (fix or feature that would cause existing functionality to not work as expected)
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been published in downstream modules

ADDITIONAL NOTE
NA

[codecov]

Codecov Report

Merging #1133 (21ec10c) into develop (d717c93) will not change coverage.
The diff coverage is 100.00%.

❗ Current head 21ec10c differs from pull request most recent head d0acedd. Consider uploading reports for the commit d0acedd to get more accurate results

@@           Coverage Diff            @@
##           develop    #1133   +/-   ##
========================================
  Coverage    92.95%   92.95%           
========================================
  Files           38       38           
  Lines         2073     2073           
========================================
  Hits          1927     1927           
  Misses         146      146           

Impacted Files	Coverage Δ
run.py	96.15% <100.00%> (ø)

[mtreacy002]

@isabelcosta, @epicadk, @vj-codes, this PR is now ready for a review. Look forward to your feedback 😉.

[isabelcosta]

Suggested change

	3. run the following command to apply the update to your local db
	4. run the following command to apply the update to your local db

careful with spaces between lines, not sure this will render the way you are thinking. I viewed the source and this number does not show up

[isabelcosta]

why this change @mtreacy002 ? just asking because at the moment this came to the project, I thought it was kind of auto-generated code 🤔 but i am not sure