pl-device-test fix: do not differentiate Projector with respect to …

…state (#5683)

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------------------------------------------------------------------------------------------------------------

**Context:**

**Description of the Change:**
Use vanilla NumPy arrays in `test_projector_expectation` to avoid
differentiating `qml.Projector` with respect to the state attribute.

**Benefits:**

**Possible Drawbacks:**

**Related GitHub Issues:**

doc/releases/changelog-dev.md

@@ -99,6 +99,9 @@
 
 <h3>Bug fixes 🐛</h3>
 
+* Use vanilla NumPy arrays in `test_projector_expectation` to avoid differentiating `qml.Projector` with respect to the state attribute.
+  [(#5683)](https://github.com/PennyLaneAI/pennylane/pull/5683)
+
 * `qml.Projector` is now compatible with jax-jit.
   [(#5595)](https://github.com/PennyLaneAI/pennylane/pull/5595)
 

pennylane/devices/tests/test_compare_default_qubit.py

@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 """Tests that a device gives the same output as the default device."""
+import numpy as np
+
 # pylint: disable=no-self-use,no-member
 import pytest
 from flaky import flaky
@@ -90,10 +92,10 @@ def workload():
             [0, 1, 0, 0],
             [0, 0, 1, 0],
             [0, 0, 0, 1],
-            pnp.array([1, 1, 0, 0]) / pnp.sqrt(2),
-            pnp.array([0, 1, 0, 1]) / pnp.sqrt(2),
-            pnp.array([1, 1, 1, 0]) / pnp.sqrt(3),
-            pnp.array([1, 1, 1, 1]) / 2,
+            np.array([1, 1, 0, 0]) / np.sqrt(2),
+            np.array([0, 1, 0, 1]) / np.sqrt(2),
+            np.array([1, 1, 1, 0]) / np.sqrt(3),
+            np.array([1, 1, 1, 1]) / 2,
         ],
     )
     def test_projector_expectation(self, device, state, tol, benchmark):

requirements-ci.txt

@@ -8,7 +8,7 @@ autograd
 toml
 appdirs
 semantic_version
-autoray
+autoray>=0.6.1,<0.6.10
 matplotlib
 requests
 tomli # Drop once minimum Python version is 3.11

requirements.txt

@@ -9,7 +9,7 @@ autograd~=1.4
 toml~=0.10
 appdirs~=1.4
 semantic_version~=2.10
-autoray>=0.6.1
+autoray>=0.6.1,<0.6.10
 matplotlib~=3.5
 opt_einsum~=3.3
 requests~=2.31.0