Fix tuple to list error

[hexu33]

Objective of pull request: Fix AttributeError: 'tuple' object has no attribute 'tolist' in src/lava/proc/conv/utils.py

Pull request checklist

Your PR fulfills the following requirements:

• Docs reviewed and added / updated if needed (for bug fixes / features)
• PR conforms to Coding Conventions
• PR applys BSD 3-clause or LGPL2.1+ Licenses to all code files
• Lint (flakeheaven lint src/lava tests/) and (bandit -r src/lava/.) pass locally
• Build tests (pytest) passes locally

Pull request type

Please check your PR type:

• Bugfix

What is the current behavior?

• When using the conv() api in the utils, there will be log error which says,
  AttributeError: 'tuple' object has no attribute 'tolist'

What is the new behavior?

• conv() in utils.py could be used successfully with no error.

Does this introduce a breaking change?

• Yes
• No

Supplemental information

[bamsumit]

Hi @hexu33 looks good. Thank you for the fix. Please also add a description of the existing error. I can see where you are getting errors, but its good to document it.