feat(ec2): provide link for customer to view system logs

[Hweinstock]

Problem

Limited ability to diagnose problems with EC2 instances provided in the toolkit.

Solution

Add a right click option to provide system log of Ec2 instance in read-only file view.

Implementation Details

• Log view does NOT live update. This would require refactoring the CWL significantly. Better to get the feature out and see if this is something customers want/need.
• To reduce code duplication two new utility components were added decodeBase64 incore/src/shared/utilities/textUtilities.ts and UriSchema in core/src/shared/utilities/uriUtils.ts.
• decodeBase64 is a helper function to wrap the use of Buffer.from(X, "base64").toString() throughout the toolkit.
• UriSchema provides a general framework for translating between an object and an URI, and vice versa. It allows us to avoid writing the isValid method in all cases. With more work this could likely be more general, but is only used twice so unclear if it is worth pursuing.
• These changes involved changing some function calls, especially in the CWL code, but does not impact functionality.

Pictures

---

License: I confirm that my contribution is made under the terms of the Apache 2.0 license.

[github-actions]

This pull request implements a feature or fix, so it must include a changelog entry. See CONTRIBUTING.md#changelog for instructions.