Create tests for `vessel-charging/messages/DeclineMessageParams` using jest

[mariolo1985]

Description

Created a Jest test to check the serialize and deserialize methods return the expected object.

Related Issue

https://github.com/DAVFoundation/dav-js/issues/26

Motivation and Context

To validate our expected results are returning correctly.

How Has This Been Tested?

This has been tested by running command npm run jest

Screenshots (if appropriate):

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [x] I have read the CONTRIBUTING document.
• [x] I have added tests to cover my changes.
• [x] All new and existing tests passed.

[mariolo1985]

Did not merge my change into my forked master.

[mariolo1985]

New PR opened: https://github.com/DAVFoundation/dav-js/pull/60