fix(pt): detach coord when building nlist in DPA-2 (#4387)

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## Summary by CodeRabbit

- **New Features**
- Enhanced memory optimization during computations in the descriptor
class.
- Streamlined selection parameter updates for improved clarity and
maintainability.
  
- **Bug Fixes**
- Retained error handling for input validation in parameter
initialization.

- **Documentation**
- Updated comments and documentation strings for better clarity on
methods and parameters.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Signed-off-by: Jinzhe Zeng <jinzhe.zeng@rutgers.edu>

deepmd/pt/model/descriptor/dpa2.py

@@ -757,7 +757,7 @@ def forward(
         nall = extended_coord.view(nframes, -1).shape[1] // 3
         # nlists
         nlist_dict = build_multiple_neighbor_list(
-            extended_coord,
+            extended_coord.detach(),
             nlist,
             self.rcut_list,
             self.nsel_list,