[docs] fix links to kak decomposition demo

pennylane/labs/dla/cartan_subalgebra.py

@@ -76,7 +76,7 @@ def cartan_subalgebra(
     A non-unique CSA is a maximal Abelian subalgebra in the horizontal subspace :math:`\mathfrak{m}` of a Cartan decomposition.
     Note that this is sometimes called a horizontal CSA, and is different from the definition of a CSA on `Wikipedia <https://en.wikipedia.org/wiki/Cartan_subalgebra>`__.
 
-    .. seealso:: :func:`~cartan_decomp`, :func:`~structure_constants`, `The KAK theorem (demo) <https://pennylane.ai/qml/demos/tutorial_kak_theorem>`__
+    .. seealso:: :func:`~cartan_decomp`, :func:`~structure_constants`, `The KAK decomposition  theory(demo) <https://pennylane.ai/qml/demos/tutorial_kak_decomposition>`__, `The KAK decomposition in practice (demo) <https://pennylane.ai/qml/demos/tutorial_fixed_depth_hamiltonian_simulation_via_cartan_decomposition>`__.
 
     Args:
         g (List[Union[PauliSentence, np.ndarray]]): Lie algebra :math:`\mathfrak{g}`, which is assumed to be ordered as :math:`\mathfrak{g} = \mathfrak{k} \oplus \mathfrak{m}`

pennylane/labs/dla/variational_kak.py

@@ -82,7 +82,7 @@ def Kc(theta_opt: Iterable[float], k: Iterable[Operator]):
     Instead of relying on having Pauli words, we use the adjoint representation
     for a more general evaluation of the cost function. The rest is the same.
 
-    .. seealso:: `Theory demo on KAK theorem <https://pennylane.ai/qml/demos/tutorial_kak_theorem>`__, `demo on KAK decomposition in practice <https://pennylane.ai/qml/demos/tutorial_fixed_depth_hamiltonian_simulation_via_cartan_decomposition>`__,
+    .. seealso:: `The KAK decomposition  theory(demo) <https://pennylane.ai/qml/demos/tutorial_kak_decomposition>`__, `The KAK decomposition in practice (demo) <https://pennylane.ai/qml/demos/tutorial_fixed_depth_hamiltonian_simulation_via_cartan_decomposition>`__.
 
     Args:
         H (Union[Operator, PauliSentence, np.ndarray]): Hamiltonian to decompose