➕ Install peft for prompt adapter support

[prashantgupta24]

For allowing PEFT adapters to be loaded, we will need the peft library installed.

Upstream PR: vllm-project#8123

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[prashantgupta24]

/retest

[dtrifiro]

/lgtm

This pass after #126 #127 is merged

[openshift-ci]

New changes are detected. LGTM label has been removed.

[dtrifiro]

Sorry if I get back to this, but I just realized this is something which is only supported in the adapter, right? In that case this should be a dependency in vllm-tgis-adapter and not something installed here.

[prashantgupta24]

This is something that is needed by vllm explicitly -

vllm/vllm/prompt_adapter/models.py

Line 93 in 7a21f52

from peft.utils import load_peft_weights

[prashantgupta24]

Also see these lines within PromptAdapterConfig:

vllm/vllm/config.py

Lines 1334 to 1340 in 7a21f52

	library_name = 'peft'
	try:
	__import__(library_name)
	except ImportError as e:
	raise ImportError(
	f"'{library_name}' is not installed for prompt adapter support."
	f"Please install it using 'pip install {library_name}'."

[maxdebayser]

I can confirm that this is needed to run the upstream unit tests.

[prashantgupta24]

Will try to get it merged in upstream https://github.com/vllm-project/vllm/pull/8123/files