lib-user: Remove the welcome elements from UserHome

[goplayoutside3]

Package

lib-user

Linked Issue and/or Talk Post

Slack

Describe your changes

• Remove the welcome modal, the link to the explanatory blog post, and the “new” label on Your Stats button.

How to Review

• Run the signed-in homepage via app-root or lib-user.

Checklist

PR Creator - Please cater the checklist to fit the review needed for your code changes.
PR Reviewer - Use the checklist during your review. Each point should be checkmarked or discussed before PR approval.

General

• Tests are passing locally and on Github
• Documentation is up to date and changelog has been updated if appropriate
• You can yarn panic && yarn bootstrap or docker-compose up --build and FEM works as expected
• FEM works in all major desktop browsers: Firefox, Chrome, Edge, Safari (Use Browserstack account as needed)

[coveralls]

coverage: 77.385% (-0.008%) from 77.393%
when pulling dd0b81c on remove-welcome-elements
into 532f964 on master.