test: Pluto.migrations updating to vi

[curtis-h]

Description:

Moving tests away from old style chai / sinon implementation to vitest.
Slight simplification to use specific models instead of using the Repositories to generate them.

Checklist:

• My PR follows the contribution guidelines of this project
• My PR is free of third-party dependencies that don't comply with the Allowlist
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I have checked the PR title to follow the conventional commit specification

[github-actions]

Lines	Statements	Branches	Functions
	76.12% (3648/4792)	66.53% (1676/2519)	80.35% (867/1079)

[coveralls]

coverage: 72.571% (+0.01%) from 72.557%
when pulling bf48021 on test/pluto-tidy
into 00ddc08 on main.

[elribonazo]

@amagyar-iohk Don't really like blocking PR's because coverage dropped 0.04