Update roadmap read.me to link to milestones

[jessicadaugherty]

Rather than listing milestones both here and on the milestones page, I've updated this read.me to link back to the milestones page

Description

Issue

Fixes #<issue_number>

Type of change

Please mark the relevant option(s):

• New feature, functionality or library
• Bug fix
• Code health or cleanup
• Major breaking change
• Documentation
• Other

List of changes

• Change prop: the agreed upon repository structure #1
• Change Version Number #2
• ...

Testing

• make develop_test
• LocalNet w/ all of the steps outlined in the README

Required Checklist

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have tested my changes using the available tooling
• I have updated the corresponding CHANGELOG

If Applicable Checklist

• I have updated the corresponding README(s); local and/or global
• I have added tests that prove my fix is effective or that my feature works
• I have added, or updated, mermaid.js diagrams in the corresponding README(s)
• I have added, or updated, documentation and mermaid.js diagrams in shared/docs/* if I updated shared/*README(s)

[andrewnguyen22]

@jessicadaugherty since you are the author, you need to merge according to our process

[Olshansk]

@jessicadaugherty Let's merge this in.