Investigate using mock services for tests

[scottwernervt]

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Investigate using mock services to mimic behaviour to improve pull request quality and rate limiting errors (#33).

• [ ] Amazon S3
  • [ ] https://www.minio.io/gcp.html
  • [ ] https://github.com/spulec/moto
  • [ ] https://github.com/adobe/S3Mock
• [ ] Azure
  • [ ] https://www.minio.io/azure.html
  • [ ] https://docs.microsoft.com/en-us/azure/storage/common/storage-use-emulator
• [ ] Google
  • [ ] https://www.minio.io/gcp.html
• [ ] Minio
  • [ ] https://www.minio.io/
• [ ] Rackspace