fix DecoderOnlyEmbedderICLSameDatasetTrainDataset category index error

[billvsme]

When I was fine-tuning use the code in the documentation for bge-en-icl, an error occurred.

error like:

[rank2]:     batch_raw_data['category'][i],  # use category as example
[rank2]: IndexError: list index out of range

Looking at the source code, I found that it was due to the for loop i variable in DecoderOnlyEmbedderICLSameDatasetTrainDataset._create_batch_data being overridden by the new for loop i variable inside.

FlagEmbedding/FlagEmbedding/finetune/embedder/decoder_only/icl/dataset.py

Lines 68 to 69 in 9abcfc8

	for i in range(len(batch_raw_data['query'])):
	if data_type is not None:

FlagEmbedding/FlagEmbedding/finetune/embedder/decoder_only/icl/dataset.py

Lines 116 to 117 in 9abcfc8

	for i in range(len(tmp_passages)):
	tmp_passages[i] += self.args.icl_suffix_str

I modified the variable name of the inner for loop, i -> j, fix this bug.