Fixes Ground Initialization Height Translation in Factory Environment

[louislelay]

Description

The table in the factory environment was initially positioned halfway into the ground due to an incorrect height translation. This PR corrects the initialization height to properly align the table with the ground, resolving the issue.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Screenshots

Before	After

Checklist

• I have run the pre-commit checks with ./isaaclab.sh --format
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• I have updated the changelog and the corresponding version in the extension's config/extension.toml file
• I have added my name to the CONTRIBUTORS.md or my name already exists there