build(deps): bump DiffEngine from 6.4.7 to 6.4.8 in /src (#298)

Bumps [DiffEngine](https://github.com/VerifyTests/DiffEngine) from 6.4.7 to 6.4.8.
- [Release notes](https://github.com/VerifyTests/DiffEngine/releases)
- [Commits](https://github.com/VerifyTests/DiffEngine/commits)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>