fix: unmark eval_pd as abstractmethod (deepmodeling#4438)

Many classes don't have this method and become abstract classes. It
looks to me like these tests are skipped silently and don't throw
errors.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

## Summary by CodeRabbit

- **Bug Fixes**
- Updated the `eval_pd` method to provide a clearer indication of its
implementation status by raising a `NotImplementedError`.
- Changed the `skip_pd` class variable to always skip Paddle-related
tests.

- **Tests**
- Adjusted the `skip_pd` property in the `TestSeA` and `TestEner`
classes to directly reflect the installation status of Paddle.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Signed-off-by: Jinzhe Zeng <[email protected]>

source/tests/consistent/common.py

@@ -101,7 +101,7 @@ class CommonTest(ABC):
     # we may usually skip jax before jax is fully supported
     skip_jax: ClassVar[bool] = True
     """Whether to skip the JAX model."""
-    skip_pd: ClassVar[bool] = not INSTALLED_PD
+    skip_pd: ClassVar[bool] = True
     """Whether to skip the Paddle model."""
     skip_array_api_strict: ClassVar[bool] = True
     """Whether to skip the array_api_strict model."""
@@ -185,7 +185,6 @@ def eval_jax(self, jax_obj: Any) -> Any:
         """
         raise NotImplementedError("Not implemented")
 
-    @abstractmethod
     def eval_pd(self, pd_obj: Any) -> Any:
         """Evaluate the return value of PD.
 
@@ -194,6 +193,7 @@ def eval_pd(self, pd_obj: Any) -> Any:
         pd_obj : Any
             The object of PD
         """
+        raise NotImplementedError("Not implemented")
 
     def eval_array_api_strict(self, array_api_strict_obj: Any) -> Any:
         """Evaluate the return value of array_api_strict.

source/tests/consistent/descriptor/test_se_e2_a.py

@@ -136,7 +136,7 @@ def skip_pd(self) -> bool:
             precision,
             env_protection,
         ) = self.param
-        return CommonTest.skip_pd
+        return not INSTALLED_PD
 
     @property
     def skip_array_api_strict(self) -> bool:

source/tests/consistent/fitting/test_ener.py

@@ -135,7 +135,7 @@ def skip_pd(self) -> bool:
         ) = self.param
         # Paddle do not support "bfloat16" in some kernels,
         # so skip this in CI test
-        return CommonTest.skip_pd or precision == "bfloat16"
+        return not INSTALLED_PD or precision == "bfloat16"
 
     tf_class = EnerFittingTF
     dp_class = EnerFittingDP