Remove legacy models

[DLM-unipd]

I suggest the removal of Bedrock models in Legacy state, following current AWS Model lifecycle official page:

• Claude 3 Haiku
• Claude 3.5 Haiku
• Claude 3.5 Sonnet
• Claude 3.5 Sonnet v2
• Claude 3.7 Sonnet
• Claude Opus 4
• Claude 3 (Opus) -> this should be already in end-of-life
• Llama 3.2 1B Instruct
• Llama 3.2 3B Instruct
• Llama 3.2 11B Instruct
• Llama 3.2 90B Instruct