Address lint errors after upgrading to Go 1.15 and golangci-lint 1.30

MERGE REQUEST

MR Guidelines

Overview

After upgrading to Go 1.15 and golangci-lint 1.30 a number of lint errors popped up. This MR addresses them.

Example for Visual Changes

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