Covalent-aws-plugins

Fixed

- Centos tests workflow by updating the Git version.

Changed

- Moved base executor image python script into covalent_aws_plugins/exec.py from Dockerfile

Fixed

- Fixed Dockerfile to create /covalent folder

Changed

- Update `docker.yml` with proper stable version attributes for worflow dispatch

Fixed

- Fixed Dockerfile and docker workflow syntax to build pre-release base executor images

Changed

- Adding `docker.yml` workflow to build and release stable/pre-release version of the base aws executor docker images to public ECR

Changed

- Not setting default AWS_SHARED_CREDENTIALS, using AWS_REGION then AWS_DEFAULT_REGION if not defined.

Documentation

- Added reference to RTD of aws plugins
- Added warning about not including [all] to install plugins, minor adjustments.

Changed

- Updated README to contain new UX for installing plugins