Fix Changelog LatestVersion Property

[sandrofigo]

This PR fixes the LatestVersion property on the Changelog class, adds unit tests to validate the desired behavior and fixes some typos. Includes changes from #1250

Before Fix

# Changelog
## [Unreleased]
### Added
- Some text

## [1.0.0] - 2023-02-03
### Added
- Added something

## [0.5.3] - 2023-01-02 <--- `LatestVersion` would return "0.5.3"
### Fixed
- Fixed something

After Fix

# Changelog
## [Unreleased]
### Added
- Some text

## [1.0.0] - 2023-02-03 <--- `LatestVersion` now returns "1.0.0"
### Added
- Added something

## [0.5.3] - 2023-01-02
### Fixed
- Fixed something

I confirm that the pull-request:

• Follows the contribution guidelines
• Is based on my own work
• Is in compliance with my employer