Bug fix for standalone mod switch down for CKKS

[christopherngutierrez]

Proposed changes

• Fixes issue with standalone mod switch down, which does not require rescale.
• Tested locally.

Types of changes

What types of changes does your code introduce to the Encrypted Computing SDK project?
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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update (if none of the other choices apply)

Checklist

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• I have read the CONTRIBUTING agreement
• Current formatting and unit tests / base functionality passes locally with my changes
• I have added tests that prove my fix is effective or that my feature works (if appropriate)
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in downstream modules

Further comments

Mod.py will need refactoring in the future.

[kylanerace]

OK Testing on E2E to prepare for full workload, will update with review when complete