[PT2][Inductor] Fix missing "example_value" for nodes introduced by group batch fusion (#120974)
Summary: Similar to D54140488, we fix more such bugs
Test Plan:
# unit test
```
buck2 test 'fbcode//mode/dev-nosan' fbcode//caffe2/test/inductor:group_batch_fusion
```
Cache hits: 0%. Commands: 1 (cached: 0, remote: 0, local: 1)
Tests finished: Pass 9. Fail 0. Fatal 0. Skip 0. Build failure 0
# local reproduce
```
buck2 run mode/opt //scripts/jackiexu0313/pt2:local_model_with_pt2 -- --test_mode split_batch
```
Differential Revision: D54399360
Pull Request resolved: https://github.com/pytorch/pytorch/pull/120974
Approved by: https://github.com/jackiexu1992
