Covalent-ec2-plugin

Changed

- Now instead of throwing an error when an ssh key doesn't exist, EC2Executor will create the key pair, link it to AWS, and then use it to connect to the instance
- Updated covalent version to use a variable instead of a hard-coded value
- Updates __init__ signature kwargs replaced with parent for better documentation.
- Changed license to Apache
- Updated AWS terraform provider version to ~> 5.17
- Covalent version to be installed on the EC2 instance can now be specified by the user - including the ability to specify extras (e.g. `covalent[qiskit]`)

Fixed

- Fixed the lookup of the tfstate file
- Fixed networking due to the provider version update
- Fixed the banner which was broken in README.md when viewed from the PyPi page

Fixed

- Centos test workflow by updating git version.
- License checker workflow.

Changed

- Moved EC2 plugin specific validation to setup (checking key file existance)
- Parsing region and profile from boto3 session (determined by AWS Base Executor)
- Removed functional test executor instance in favour of config file configuration

Changed

- Removed executor defaults for boto3 session args

Changed

- Functional tests using pytest and .env file configuration

Changed

- Updated SSH plugin version to correspond with covalent >=0.202.0,<1