Upgrade major version to 3

[injoonH]

Features

• Allow all IPs to debug when DEBUG = True. PR #377 by @retroinspect.
• Squash 'QnA' and 'Anonymous' boards into 'Talk'. PR #384 by @retroinspect.
• Update run.sh to support the DX container. PR #387 by @TriangleYJ.
• Top articles when upvotes are over the threshold. PR #385 by @injoonH.
• Add test user generator. PR #385 by @injoonH.
• Use Pipenv for package management. PR #388 by @injoonH.
  • Update Dockerfile.
• Use drf_spectacular for OpenAPI 3.0 schema generation. PR #388 by @injoonH.
• Filter articles using board slug. PR #392 by @injoonH.
• Use slug for board detail looup. PR #393 by @injoonH.
• Add BoardGroup model. PR #395 by @injoonH.
• Use BoardDetailActionSerializer for board detail lookup. PR #396 by @injoonH.
• Include attachment details in the article's detailed response. PR #400 by @injoonH.

Upgrades

• Upgrade Python to 3.11. PR #388 by @injoonH.
  • Use typing features supported in Python version 3.11.
• Upgrade Django to 4.2. PR #388 by @injoonH.
• Upgrade MySQL to 8.0. PR #388 by @retroinspect.

Refactors

• Exclude unnecessary fields of Board and Topic in serializers. PR #391 by @injoonH.

Fixes

• Allow admin to post anonymous comments. PR #398 by @injoonH.

Docs

• Update package versions and package manager in README.md. PR #388 by @injoonH.

Internal

• Update environment variable CACHE_DOCKER_TAG to DJANGO_ENV. PR #388 by @injoonH.