fix: Switch to using fmt.Println

[tianfeng92]

Proposed changes

In several places, our code currently utilizes println() for outputting information.
However, println() is primarily meant for bootstrapping and debugging purposes, and it directs output to stderr. For standard output, we should switch to using fmt.Println().

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• I have updated the json schema (if appropriate)

Further comments