Docs: Fix the daemon management examples (#60)

The examples were incorrectly using `GET` requests to start and stop the
daemon, but this should be `POST` requests.

The Quantum ESPRESSO example is also updated to use the SSSP family that
is currently the default installed by `aiida-pseudo install sssp`.

examples/daemon_management/script.py

@@ -103,12 +103,12 @@ def main():
         click.echo(f"The daemon is currently running with {num_workers} workers")
 
         click.echo("Stopping the daemon.")
-        response = request("daemon/stop", method="GET")
+        response = request("daemon/stop", method="POST")
 
     else:
         click.echo("The daemon is currently not running.")
         click.echo("Starting the daemon.")
-        response = request("daemon/start", method="GET")
+        response = request("daemon/start", method="POST")
         num_workers = response["num_workers"]
         click.echo(f"The daemon is currently running with {num_workers} workers")
 

examples/submit_quantumespresso_pw/script.py

@@ -239,7 +239,7 @@ def main(workchain):
     structure_uuid = create_node("core.structure", structure)
     parameters_uuid = create_node("core.dict", parameters)
     kpoints_uuid = create_node("core.array.kpoints", kpoints)
-    pseudo_si_uuid = get_pseudo_for_element("SSSP/1.1/PBE/efficiency", "Si")["uuid"]
+    pseudo_si_uuid = get_pseudo_for_element("SSSP/1.2/PBE/efficiency", "Si")["uuid"]
 
     if workchain:
         # Inputs for a ``PwBaseWorkChain`` to compute SCF of Si crystal structure