Feature/prepend bos padding side brdige

[jlarson4]

Description

• Added more explicit warnings if users attempt to use padding_side or prepend_bos on TransformerBridge, explaining why we don't have those built in directly and how to do those things if needed.
• Improved intermediate hook firing when running in compatibility mode on GatedMLP

Type of change

• New feature (non-breaking change which adds functionality)

Checklist:

• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have not rewritten tests relating to key interfaces which would affect backward compatibility