Resolve "Add siac command for /skynet/blacklist GET endpoint"

MERGE REQUEST

MR Guidelines

Overview

Not too helpful the siac skynet blacklist get command only returning merkleroots. Knowing the bitfield we could calculate the offset/length and use NewSkylinkV1 to get the skylink, but I don't see any way to get this information. So far get is just returning the same as the API.

Other than that, let me know if there are issues or comments!

Example for Visual Changes

https://asciinema.org/a/Fn7d0b1Wx9X7WlBTBCsEE6QOZ

Checklist

Review and complete the checklist to ensure that the MR is complete before assigned to an approver.

• All new methods or updated methods have clear docstrings
• Testing added or updated for new methods
• Any new packages are added to Makefile and .gitlab-ci.yml
• API documentation updated for API updates
• Module README.md updated for changes to workflow
• Issue added to Sia-UI repo for new supporting features
• Changelog File Created

Issues Closed

Closes #4005 (closed)