Fix quickstart by using docker-compose run and docker network for all commands

[NevilleS]

Purpose

This is a subtle thing, but in trying to reproduce some of the issues on main (e.g. #1055, probably also #1054) I saw we were mixing & matching using docker-compose and docker exec. If we use compose thoroughly, we'll find that the docker network is more predictable for service names, etc.

Changes

• Edits noxfile commands to use docker-compose run for interactive sessions
• Tweaks quickstart.py to reference webserver host name instead of localhost (since it creates a one-off container using docker-compose run now)

Checklist

• Update CHANGELOG.md file
  • Merge in main so the most recent CHANGELOG.md file is being appended to
  • Add description within the Unreleased section in an appropriate category. Add a new category from the list at the top of the file if the needed one isn't already there.
  • Add a link to this PR at the end of the description with the PR number as the text. example: #1
• Applicable documentation updated (guides, quickstart, postman collections, tutorial, fidesdemo, database diagram.
• If docs updated (select one):
  • documentation complete, or draft/outline provided (tag docs-team to complete/review on this branch)
  • documentation issue created (tag docs-team to complete issue separately)
• Good unit test/integration test coverage
• This PR contains a DB migration. If checked, the reviewer should confirm with the author that the down_revision correctly references the previous migration before merging
• The Run Unsafe PR Checks label has been applied, and checks have passed, if this PR touches any external services

Ticket

Fixes #1055
Fixes #1054