[CI] Fix transformer xl (PaddlePaddle#5255)

* [CI] fix transformer-xl

* Update

Author: zjjlivein

scripts/regression/ci_case.sh

@@ -884,7 +884,9 @@ print_info $? ernie-doc_dureader_robust
 #26 transformer-xl
 transformer-xl (){
 cd ${nlp_dir}/examples/language_model/transformer-xl/
-cp -r /ssd1/paddlenlp/download/transformer-xl/* ./
+mkdir gen_data && cd gen_data
+wget https://paddle-qa.bj.bcebos.com/paddlenlp/enwik8.tar.gz && tar -zxvf enwik8.tar.gz
+cd ../
 export CUDA_VISIBLE_DEVICES=${cudaid2}
 time (sed -i 's/print_step: 100/print_step: 1/g' configs/enwik8.yaml
 sed -i 's/save_step: 10000/save_step: 3/g' configs/enwik8.yaml