Fixed a code typo in 02_operators_overview.ipynb (#1231)

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### Summary
Fix a typo, in cell with description "# Compose YX in front of the
previous operator". The code compose XZ in front of the previous
operator, while it should be YX.


### Details and comments
`op.compose(XZ, qargs=[0, 2], front=True)` is changed with
`op.compose(YX, qargs=[0, 2], front=True)`, and add the correct output.

---------

Co-authored-by: Eric Arellano <[email protected]>

Author: elberttl

tutorials/circuits_advanced/01_advanced_circuits.ipynb

@@ -605,7 +605,7 @@
     "\n",
     "qc.append(sub_circ2.to_instruction(), [qr[2], qr[3]])\n",
     "\n",
-    "print(qc.draw())\n",
+    "qc.draw()\n",
     "\n",
     "# The following raises an error: \"QiskitError: 'Name conflict on adding parameter: phi'\"\n",
     "# phi2 = Parameter('phi')\n",
@@ -692,9 +692,9 @@
     "larger_qc.append(qc.to_instruction({p: theta}), qr[0:3])\n",
     "larger_qc.append(qc.to_instruction({p: phi}), qr[3:6])\n",
     "larger_qc.append(qc.to_instruction({p: gamma}), qr[6:9])\n",
-    "print(larger_qc.draw())\n",
+    "larger_qc.draw()\n",
     "\n",
-    "print(larger_qc.decompose().draw())"
+    "larger_qc.decompose().draw()"
    ]
   },
   {

tutorials/circuits_advanced/02_operators_overview.ipynb

@@ -777,7 +777,7 @@
     }
    ],
    "source": [
-    "# Compose XZ with an 3-qubit identity operator\n",
+    "# Compose XZ with a 3-qubit identity operator\n",
     "op = Operator(np.eye(2 ** 3))\n",
     "XZ = Operator(Pauli('XZ'))\n",
     "op.compose(XZ, qargs=[0, 2])"
@@ -796,22 +796,14 @@
     {
      "data": {
       "text/plain": [
-       "Operator([[ 0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  1.+0.j,  0.+0.j,  0.+0.j,\n",
-       "            0.+0.j],\n",
-       "          [ 0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j, -1.+0.j,  0.+0.j,\n",
-       "            0.+0.j],\n",
-       "          [ 0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  1.+0.j,\n",
-       "            0.+0.j],\n",
-       "          [ 0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,\n",
-       "           -1.+0.j],\n",
-       "          [ 1.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,\n",
-       "            0.+0.j],\n",
-       "          [ 0.+0.j, -1.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,\n",
-       "            0.+0.j],\n",
-       "          [ 0.+0.j,  0.+0.j,  1.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,\n",
-       "            0.+0.j],\n",
-       "          [ 0.+0.j,  0.+0.j,  0.+0.j, -1.+0.j,  0.+0.j,  0.+0.j,  0.+0.j,\n",
-       "            0.+0.j]],\n",
+       "Operator([[0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.-1.j, 0.+0.j, 0.+0.j],\n",
+       "          [0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.-1.j, 0.+0.j, 0.+0.j, 0.+0.j],\n",
+       "          [0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.-1.j],\n",
+       "          [0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.-1.j, 0.+0.j],\n",
+       "          [0.+0.j, 0.+1.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j],\n",
+       "          [0.+1.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j],\n",
+       "          [0.+0.j, 0.+0.j, 0.+0.j, 0.+1.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j],\n",
+       "          [0.+0.j, 0.+0.j, 0.+1.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j, 0.+0.j]],\n",
        "         input_dims=(2, 2, 2), output_dims=(2, 2, 2))"
       ]
      },
@@ -824,7 +816,7 @@
     "# Compose YX in front of the previous operator\n",
     "op = Operator(np.eye(2 ** 3))\n",
     "YX = Operator(Pauli('YX'))\n",
-    "op.compose(XZ, qargs=[0, 2], front=True)"
+    "op.compose(YX, qargs=[0, 2], front=True)"
    ]
   },
   {