fix: Removed a wrong key-word argument in sigmoid_focal_loss() function call

[Sai-Suraj-27]

What does this PR do?

The reduction argument passed in the following function call is wrong. We can see from the function definition of sigmoid_focal_loss there is no parameter named reduction:

transformers/src/transformers/models/rt_detr/modeling_rt_detr.py

Line 2166 in 7f79a97

loss = sigmoid_focal_loss(src_logits, target, self.alpha, self.gamma, reduction="none")

transformers/src/transformers/models/rt_detr/modeling_rt_detr.py

Lines 1933 to 1950 in 7f79a97

	def sigmoid_focal_loss(inputs, targets, num_boxes, alpha: float = 0.25, gamma: float = 2):
	"""
	Loss used in RetinaNet for dense detection: https://arxiv.org/abs/1708.02002.
	Args:
	inputs (`torch.FloatTensor` of arbitrary shape):
	The predictions for each example.
	targets (`torch.FloatTensor` with the same shape as `inputs`)
	A tensor storing the binary classification label for each element in the `inputs` (0 for the negative class
	and 1 for the positive class).
	alpha (`float`, *optional*, defaults to `0.25`):
	Optional weighting factor in the range (0,1) to balance positive vs. negative examples.
	gamma (`int`, *optional*, defaults to `2`):
	Exponent of the modulating factor (1 - p_t) to balance easy vs hard examples.
	Returns:
	Loss tensor
	"""

Fixes # (issue)

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Who can review?

@ArthurZucker @amyeroberts

[amyeroberts]

Thanks for fixing!