Remove custome_container for building the docs

[albertvillanova]

Remove custome_container for building the docs:

• Fix DDPO ImportError: cannot import name 'FLAX_WEIGHTS_NAME'

This PR makes a small update to the GitHub Actions workflows for building documentation. The change removes the use of a custom Docker container for the documentation build jobs.

Currently the CI GitHub Action to build the main docs is broken, due to an issue with the versions of diffusers and transformers: https://github.com/huggingface/trl/actions/runs/18184074495/job/51765142515

ImportError: cannot import name 'FLAX_WEIGHTS_NAME' from 'transformers.utils' (/usr/local/lib/python3.10/site-packages/transformers/utils/__init__.py)

After investigation:

• the issue is already fixed in diffusers but not released yet:
  • [CI] Fix TRANSFORMERS_FLAX_WEIGHTS_NAME import issue diffusers#12354
• the root cause in transformers is on main but not released yet (as of 4.56.2):
  • 🚨🚨🚨 Fully remove Tensorflow and Jax support library-wide transformers#40760
• the issue with our GH Action building the main doc is that it uses a custom Docker container (huggingface/transformers-doc-builder), where transformers is installed from main: transformers-4.57.0.dev0

Traceback:

Building the MDX files:   2%|▏         | 1/55 [00:05<04:52,  5.42s/it]
Traceback (most recent call last):
  File "/usr/local/lib/python3.10/site-packages/trl/import_utils.py", line 144, in _get_module
    return importlib.import_module("." + module_name, self.__name__)
  File "/usr/local/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 688, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 883, in exec_module
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "/usr/local/lib/python3.10/site-packages/trl/models/modeling_sd_base.py", line 25, in <module>
    from diffusers import DDIMScheduler, StableDiffusionPipeline, UNet2DConditionModel
  File "/usr/local/lib/python3.10/site-packages/diffusers/__init__.py", line 911, in <module>
    from .modular_pipelines import ComponentsManager, ComponentSpec, ModularPipeline, ModularPipelineBlocks
  File "/usr/local/lib/python3.10/site-packages/diffusers/modular_pipelines/__init__.py", line 60, in <module>
    from .flux import FluxAutoBlocks, FluxModularPipeline
  File "/usr/local/lib/python3.10/site-packages/diffusers/modular_pipelines/flux/__init__.py", line 44, in <module>
    from .encoders import FluxTextEncoderStep
  File "/usr/local/lib/python3.10/site-packages/diffusers/modular_pipelines/flux/encoders.py", line 27, in <module>
    from ..modular_pipeline import ModularPipelineBlocks, PipelineState
  File "/usr/local/lib/python3.10/site-packages/diffusers/modular_pipelines/modular_pipeline.py", line 31, in <module>
    from ..pipelines.pipeline_loading_utils import _fetch_class_library_tuple, simple_get_class_obj
  File "/usr/local/lib/python3.10/site-packages/diffusers/pipelines/__init__.py", line 504, in <module>
    from .auto_pipeline import (
  File "/usr/local/lib/python3.10/site-packages/diffusers/pipelines/auto_pipeline.py", line 23, in <module>
    from .aura_flow import AuraFlowPipeline
  File "/usr/local/lib/python3.10/site-packages/diffusers/pipelines/aura_flow/__init__.py", line 35, in <module>
    from .pipeline_aura_flow import AuraFlowPipeline
  File "/usr/local/lib/python3.10/site-packages/diffusers/pipelines/aura_flow/pipeline_aura_flow.py", line 35, in <module>
    from ..pipeline_utils import DiffusionPipeline, ImagePipelineOutput
  File "/usr/local/lib/python3.10/site-packages/diffusers/pipelines/pipeline_utils.py", line 76, in <module>
    from .pipeline_loading_utils import (
  File "/usr/local/lib/python3.10/site-packages/diffusers/pipelines/pipeline_loading_utils.py", line 51, in <module>
    from transformers.utils import FLAX_WEIGHTS_NAME as TRANSFORMERS_FLAX_WEIGHTS_NAME
ImportError: cannot import name 'FLAX_WEIGHTS_NAME' from 'transformers.utils' (/usr/local/lib/python3.10/site-packages/transformers/utils/__init__.py)

[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

[albertvillanova]

Also note that with this change, the building doc action takes less total time:

• Before: 3m 37s
  • Step: Initialize containers: 1m 42 s
• Now: 1m 53s
  • No Intialize containers step

[albertvillanova]

This PR is ready for review. Once merged, I can take care of re-triggering the action to create the docs for the 0.23.1 release.

CC: @kashif @lewtun @qgallouedec