Drop AbstractSingleton as a parent class of the vector memory

[collijk]

Background

Singletons are bad and we don't need them

Changes

• Remove the abstract singleton parent class from the vector memory

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

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[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: -0.10 ⚠️

Comparison is base (8bce027) 50.29% compared to head (97adeff) 50.20%.

❗ Current head 97adeff differs from pull request most recent head c21f14c. Consider uploading reports for the commit c21f14c to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4901      +/-   ##
==========================================
- Coverage   50.29%   50.20%   -0.10%     
==========================================
  Files         116      116              
  Lines        4843     4808      -35     
  Branches      653      645       -8     
==========================================
- Hits         2436     2414      -22     
+ Misses       2221     2215       -6     
+ Partials      186      179       -7     

Impacted Files	Coverage Δ
autogpt/memory/vector/providers/base.py	96.42% <100.00%> (-0.13%)	⬇️

... and 21 files with indirect coverage changes

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[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.