[CI] Add LTV support for Renderer and HRTF binary tests + Python scripts fixes

• Related issues: N/A
• Requested reviewers: @kiene

Reason why this change is needed

• Fixes some bugs in the python scripts and adds support for using LTVs or cut LTVs for the renderer/HRTF binary tests

Description of the change

• Added LTV support to tests/renderer and tests/hrtf_binary_loading
• Fixed a potential bug in cut_pcm.py when the length specified is larger than the file
• Fix a crash with batch_comp_audio.py when MLD is in PATH (which is what batch_comp_audio.py checks) but not in scripts/tools/PLATFORM

Affected operating points

• N/A