Set up for dot-env.

[JoeZiminski]

This PR allows python-dotenv to be used to set environment variables for the AWS and GDrive tests. This makes it much easier to run the tests locally.

[Copilot]

Pull request overview

This PR adds support for python-dotenv to enable easier local testing of AWS and GDrive functionality by allowing developers to store test credentials in a .env file. The changes maintain backward compatibility with GitHub Actions while providing a more convenient way to manage test credentials locally.

• Adds python-dotenv integration to load environment variables from a .env file
• Updates documentation in test utility functions to explain the dotenv usage
• Adds .env to .gitignore to prevent accidental credential commits

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 2 comments.

File	Description
.gitignore	Adds .env file exclusion to prevent test credentials from being committed
tests/tests_transfers/aws/aws_test_utils.py	Imports and uses load_dotenv() for loading AWS test credentials, updates documentation and fixes "GitHub" capitalization
tests/tests_transfers/gdrive/gdrive_test_utils.py	Imports and uses load_dotenv() for loading GDrive test credentials, adds documentation about dotenv usage

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[Copilot]

The logic here will incorrectly return False if environment variables are set manually (not via .env file) when not running on GitHub Actions. The load_dotenv() function returns False when no .env file is found, even if the required environment variables are already set in the environment. Consider calling load_dotenv() without checking its return value, or restructure the logic to only use load_dotenv() as an attempt to load variables, not as a requirement.

Suggested change

	if not load_dotenv():
	return False
	# Best-effort load from .env for local development; ignore return value
	load_dotenv()

[Copilot]

The logic here will incorrectly return False if environment variables are set manually (not via .env file) when not running on GitHub Actions. The load_dotenv() function returns False when no .env file is found, even if the required environment variables are already set in the environment. Consider calling load_dotenv() without checking its return value, or restructure the logic to only use load_dotenv() as an attempt to load variables, not as a requirement.

Suggested change

	if not load_dotenv():
	return False
	# Attempt to load variables from a .env file if present, but do not
	# treat the absence of a .env file as a failure condition.
	load_dotenv()