fix emb script(#5345)

Author: tastelikefeet

examples/train/embedding/train_emb.sh

@@ -5,7 +5,10 @@ nproc_per_node=2
 # --use_chat_template must be false to use generation template
 # --dataloader_drop_last must be true or eval gather will throw error
 # --model iic/gte-modernbert-base iic/gte_Qwen2-7B-instruct also supported
+# INFONCE_TEMPERATURE default value is 0.01, here we use 0.1 because it makes
+# the `sentence-transformers/stsb:positive` dataset result to a zero loss
 CUDA_VISIBLE_DEVICES=0,1 \
+INFONCE_TEMPERATURE=0.1 \
 NPROC_PER_NODE=$nproc_per_node \
 swift sft \
     --model Qwen/Qwen3-Embedding-0.6B \