Update v2 with v1 demonstrations (#1419)

## Summary
Update `v2` with/ changes to `v1` demonstrations directory using `qml
sync-v2` with @rashidnhm 's recent updates to the demo.

---------

Co-authored-by: Andrija Paurevic <46359773+andrijapau@users.noreply.github.com>

Author: Alan-eMartin

demonstrations_v2/tutorial_iqp_circuit_optimization_jax/demo.py

@@ -552,8 +552,8 @@ def loss_fn(params, circuit, ops, n_samples, key):
 # machinery. We can then compare our trained and untrained samples with the ground truth through a
 # histogram of the bitstring weights and evaluate the distributions.
 #
-samples_untrained = circuit.sample(params_init, 1000)
-samples_trained = circuit.sample(trainer.final_params, 1000)
+samples_untrained = circuit.sample(params_init, shots=1000)
+samples_trained = circuit.sample(trainer.final_params, shots=1000)
 
 plt.hist(np.sum(samples_untrained, axis=1), bins=20, range=[0,20], alpha=0.5, label = 'untrained circuit')
 plt.hist(np.sum(samples_trained, axis=1), bins=20, range=[0,20], alpha=0.5, label = 'trained circuit')