Adds handtracking teleop device for galbot left arm stack cube task

[rebeccazhang0707]

Description

As requested by SQA engineer, "handtracking" is added in teleop device list for both agibot and galbot tasks.

Also, removed an unnecessary rendering config to enable dlss.

Type of change

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

Checklist

• I have read and understood the contribution guidelines
• 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