Issues in the contributing guidelines

[LeonLuttenberger]

Is your idea related to a problem? Please describe.

I found the following issues with the contributing guidelines:

1. When deploying aws-data-wrangler-databases, CloudFormation failed when creating the CodeBuildTestRoleLFPermissions resource with Resource does not exist or requester is not authorized to access requested permissions.. The issue was that the IAM role used to create the CloudFormation stack did not have Lake Formation permission needed to grant permissions.
2. With the full test environment, the guide specific that running pytest -n 8 tests/test_db.py will run all the database related tests. However, test_db.py does not exist.

Describe the solution you'd like

1. An entry could be added to the CONTRIBUTING_COMMON_ERRORS page which specifies that the IAM role used by CloudFormation needs to be added as a Lake Formation admin. The troubleshooting guide can say "find the role prefixed with cdk-hnb659fds-cfn-exec-role- and add it as an admin".
2. Update the guidelines to specify the proper unit test file