Remove dead agent manager

[collijk]

Background

The AgentManager is dead code (and a confusing abstraction to begin with). It is also one of the last few singletons in the system.

Changes

• Remove the dead AgentManager code and tests

Documentation

N/A

Test Plan

CI

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	5918bbe
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[Pwuts]

Sub-agents are still listed as an available resource in prompt_settings.yml

[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (f6da992) 50.55% compared to head (5918bbe) 50.56%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4900   +/-   ##
=======================================
  Coverage   50.55%   50.56%           
=======================================
  Files         116      115    -1     
  Lines        4860     4790   -70     
  Branches      657      636   -21     
=======================================
- Hits         2457     2422   -35     
+ Misses       2219     2192   -27     
+ Partials      184      176    -8     

Impacted Files	Coverage Δ
autogpt/agent/__init__.py	100.00% <100.00%> (ø)

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[github-actions]

This pull request has conflicts with the base branch, please resolve those so we can evaluate the pull request.

[github-actions]

Conflicts have been resolved! 🎉 A maintainer will review the pull request shortly.

[Auto-GPT-Bot]

You changed AutoGPT's behaviour. The cassettes have been updated and will be merged to the submodule when this Pull Request gets merged.

[Auto-GPT-Bot]

You changed AutoGPT's behaviour. The cassettes have been updated and will be merged to the submodule when this Pull Request gets merged.

[Auto-GPT-Bot]

You changed AutoGPT's behaviour. The cassettes have been updated and will be merged to the submodule when this Pull Request gets merged.