Update to using Model Optimizer (formerly AMMO) in PTQ workflow

[janekl]

What does this PR do ?

Summary:

• use Model Optimizer library (formerly AMMO) for LLM PTQ workflow
• restore PTQ tests failing due to setting apply_rope_fusion = True by default
• update documentation

Collection: NLP

Changelog

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Usage

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PR Type:

• [ ] New Feature
• [x] Bugfix
• [x] Documentation

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Additional Information

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