[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

src/qibo/tomography/gate_set_tomography.py

@@ -215,7 +215,7 @@ def execute_GST(
         if nqubits != len(gate.qubits):
             raise_error(
                 ValueError,
-                f"Mismatched inputs: nqubits given as {nqubits}. {gate} is a {len(gate.qubits)}-qubit gate."
+                f"Mismatched inputs: nqubits given as {nqubits}. {gate} is a {len(gate.qubits)}-qubit gate.",
             )
         gate = gate.__class__(*gate.qubits, **gate.init_kwargs)