[train_controlnet.py] Fix the LR schedulers when num_train_epochs is passed in a distributed training env

[Bhavay-2001]

What does this PR do?

Part of #8384

Test script

export MODEL_DIR="runwayml/stable-diffusion-v1-5"
export OUTPUT_DIR="controlnet_output"

accelerate launch train_controlnet.py \
 --pretrained_model_name_or_path=$MODEL_DIR \
 --output_dir=$OUTPUT_DIR \
 --dataset_name=fusing/fill50k \
 --resolution=512 \
 --num_train_epochs=100 \
 --learning_rate=1e-5 \
 --validation_image "./conditioning_image_1.png" "./conditioning_image_2.png" \
 --validation_prompt "red circle with blue background" "cyan circle with brown floral background" \
 --train_batch_size=4

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• Did you write any new necessary tests?

Who can review?

@sayakpaul

[Bhavay-2001]

Hi @sayakpaul, could you pls review this?

[sayakpaul]

@Bhavay-2001 when you are working on parts of issues like #8384, please don't write "Fixes ..." in your PRs because your PR doesn't fully fix the issue. It's a part of the solution, rather.

[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.

[Bhavay-2001]

Hi @sayakpaul, Please review this once.
Thanks

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the contributing guidelines are likely to be ignored.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the contributing guidelines are likely to be ignored.

[sayakpaul]

Failing test is unrelated.