(aws/lambda): Lambda functional tests

[jorgebee65]

Add some functional tests with Cypress in order to validate the AWS - Lambda functionality:

• List the functions
• Inspect the details
• Create Lambda
• Edit Lambda
• Delete Lambda

[spinnakerbot]

The following commits need their title changed:

• e7057c3: Add functional test for AWS Lambda

• 5b89549: (aws/lambda): split the tests for better visibility

Please format your commit title into the form:

<type>(<scope>): <subject>, e.g. fix(kubernetes): address NPE in status check

This allows us to easily generate changelogs & determine semantic version numbers when cutting releases. You can read more about commit conventions here.