Proposed changes

Extending AWS system tests to include a full end-to-end test by using the new robotframework-aws Robot Framework library.

• Use AWS access key (stored in github secrets) to access AWS IoT Core API (and mqtt)
• Add system tests to check AWS server generated certificates (and verify function by sending telemetry data and sending a command to thin-edge.io)
• Refactor an existing test to use the AWS.Get IoT Url to get the IoT endpoint using the provided credentials (this enables one less secret to maintain)

Note: To run the AWS tests locally you will need to create an access key in AWS and grant it permissions for all IoT actions, then set the following env variables in your .env file.

AWS_ACCESS_KEY_ID=
AWS_SECRET_ACCESS_KEY=
AWS_REGION=us-east-1

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Improvement (general improvements like code refactoring that doesn't explicitly fix a bug or add any new functionality)
• Documentation Update (if none of the other choices apply)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Paste Link to the issue

Checklist

• I have read the CONTRIBUTING doc
• I have signed the CLA (in all commits with git commit -s)
• I ran cargo fmt as mentioned in CODING_GUIDELINES
• I used cargo clippy as mentioned in CODING_GUIDELINES
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Further comments