[OpenVino BackEnd] support np.diff for ov BackEnd (keras-team#20950)

* [OpenVino BackEnd] support np.diff for ov BackEnd

* [OpenVino BackEnd] support np.diff for ov BackEnd

* [OpenVino BackEnd] support np.diff for ov BackEnd

* [OpenVino BackEnd] support np.diff for ov BackEnd

* [OpenVino BackEnd] support np.diff for ov BackEnd

* [OpenVino BackEnd] support np.diff for ov BackEnd

* [OpenVino BackEnd] support np.diff for ov BackEnd

Author: chiruu12

keras/src/backend/openvino/excluded_concrete_tests.txt

@@ -87,6 +87,11 @@ NumpyOneInputOpsCorrectnessTest::test_correlate
 NumpyOneInputOpsCorrectnessTest::test_cumprod
 NumpyOneInputOpsCorrectnessTest::test_diag
 NumpyOneInputOpsCorrectnessTest::test_diagonal
+<<<<<<< HEAD
+=======
+NumpyOneInputOpsCorrectnessTest::test_exp
+NumpyOneInputOpsCorrectnessTest::test_expand_dims
+>>>>>>> 66cc6d5a8 ([OpenVino BackEnd] support np.diff for ov BackEnd (#20950))
 NumpyOneInputOpsCorrectnessTest::test_exp2
 NumpyOneInputOpsCorrectnessTest::test_expm1
 NumpyOneInputOpsCorrectnessTest::test_flip