Fix plugin loading issues

[Pwuts]

Background

• Legacy config parameters ALLOWLISTED_PLUGINS and DENYLISTED_PLUGINS do not currently work, because Config is initialized (and therewith an empty plugins_config.yaml is created) before those config variables are loaded from .env.
• --install-plugin-deps can fail, because install_plugin_dependencies() assumes that the first named item in an archive is the base folder, which it isn't always.

Changes

• Run config.model_post_init() at the end of Configurable.build_agent_configuration instead of in Config.__init__, to make sure .env has been loaded before proceeding to model init (including PluginsConfig.load_config(config))
• Add debug logging to install_plugin_dependencies()
• Change the way install_plugin_dependencies() looks for requirements files in zipped plugins

Documentation

Test Plan

• CI
• Manually tested by @NeonN3mesis and myself

PR Quality Checklist

• My pull request is atomic and focuses on a single change.
• I have thoroughly tested my changes with multiple different prompts.
• I have considered potential risks and mitigations for my changes.
• I have documented my changes clearly and comprehensively.
• I have not snuck in any "extra" small tweaks changes.
• I have run the following commands against my code to ensure it passes our linters:

  black .
  isort .
  mypy
  autoflake --remove-all-unused-imports --recursive --ignore-init-module-imports --ignore-pass-after-docstring autogpt tests --in-place

[netlify]

✅ Deploy Preview for auto-gpt-docs canceled.

Name	Link
🔨 Latest commit	3cc8863
🔍 Latest deploy log	https://app.netlify.com/sites/auto-gpt-docs/deploys/64a5f25bf6c5ea000862a11d

[codecov]

Codecov Report

Patch coverage: 92.00% and project coverage change: +0.14 🎉

Comparison is base (0c8288b) 49.90% compared to head (3cc8863) 50.05%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4888      +/-   ##
==========================================
+ Coverage   49.90%   50.05%   +0.14%     
==========================================
  Files         116      116              
  Lines        4813     4799      -14     
  Branches      649      643       -6     
==========================================
  Hits         2402     2402              
+ Misses       2226     2218       -8     
+ Partials      185      179       -6     

Impacted Files	Coverage Δ
autogpt/config/config.py	79.13% <81.81%> (+4.47%)	⬆️
autogpt/plugins/plugins_config.py	85.96% <100.00%> (+7.63%)	⬆️

☔ View full report in Codecov by Sentry.
📢 Do you have feedback about the report comment? Let us know in this issue.