pr_8915 引入多个模型动转静报错

[EmmonsCurse]

问题确认 Search before asking

• 我已经查询历史issue，没有发现相似的bug。I have searched the issues and found no similar bug report.

Bug组件 Bug Component

No response

Bug描述 Describe the Bug

PR #8915 引入多个模型动转静报错，其中

• faster_rcnn 与 mask_rcnn 系列报错：AttributeError: 'list' object has no attribute 'shape'
• solov2 系列报错：AssertionError: 'Elements in shape must be Tensor with one element or integers.
  ...

@wanghuancoder @lyuwenyu @jerrywgz @LokeZhou 辛苦协助跟进一下～

复现环境 Environment

复现环境：

• OS: Linux
• PaddlePaddle: develop
• PaddleDetection: develop(pr_8915 合入后)

复现方法：

• 安装适配自己环境的 Paddle whl 包

git clone https://github.com/PaddlePaddle/PaddleDetection.git -b develop
cd PaddleDetection

python setup.py install

python tools/export_model.py -c configs/faster_rcnn/faster_rcnn_r50_vd_fpn_2x_coco.yml --output_dir=./inference_model -o weights=https://paddledet.bj.bcebos.com/models/faster_rcnn_r50_vd_fpn_2x_coco.pdparams

python tools/export_model.py -c configs/mask_rcnn/mask_rcnn_r50_fpn_1x_coco.yml --output_dir=./inference_model -o weights=https://paddledet.bj.bcebos.com/models/mask_rcnn_r50_fpn_1x_coco.pdparams

python tools/export_model.py -c configs/solov2/solov2_r50_fpn_1x_coco.yml --output_dir=./inference_model -o weights=https://paddledet.bj.bcebos.com/models/solov2_r50_fpn_1x_coco.pdparams

Bug描述确认 Bug description confirmation

• 我确认已经提供了Bug复现步骤、代码改动说明、以及环境信息，确认问题是可以复现的。I confirm that the bug replication steps, code change instructions, and environment information have been provided, and the problem can be reproduced.

是否愿意提交PR？ Are you willing to submit a PR?

• 我愿意提交PR！I'd like to help by submitting a PR!