Map wires #2: Add top-level qml.map_wires function

[AlbertMitjans]

NOTE: Review after the following PR is merged into master:

• Map wires #1: Add map_wires method to Operator class #3143

Added the qml.map_wires function, that changes the wires of the given operator, QNode, QuantumTape or quantum function according to the given wire map.

Using qml.map_wires with an operator:

>>> op = qml.RX(0.54, wires=0) + qml.PauliX(1) + (qml.PauliZ(2) @ qml.RY(1.23, wires=3))
>>> op
(RX(0.54, wires=[0]) + PauliX(wires=[1])) + (PauliZ(wires=[2]) @ RY(1.23, wires=[3]))
>>> wire_map = {0: 3, 1: 2, 2: 1, 3: 0}
>>> qml.map_wires(op, wire_map)
(RX(0.54, wires=[3]) + PauliX(wires=[2])) + (PauliZ(wires=[1]) @ RY(1.23, wires=[0]))

Using qml.map_wires with a QNode:

>>> dev = qml.device("default.qubit", wires=4)
>>> @qml.qnode(dev)
    def circuit():
        qml.RX(0.54, wires=0) @ qml.PauliX(1) @ qml.PauliZ(2) @ qml.RY(1.23, wires=3)
        return qml.probs(wires=0)
>>> mapped_circuit = qml.map_wires(circuit, wire_map)
>>> mapped_circuit()
tensor([0.92885434, 0.07114566], requires_grad=True)
>>> list(mapped_circuit.tape)
[((RX(0.54, wires=[3]) @ PauliX(wires=[2])) @ PauliZ(wires=[1])) @ RY(1.23, wires=[0]),
probs(wires=[3])]

[codecov]

Codecov Report

Merging #3145 (f227e98) into master (4e1aabc) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #3145   +/-   ##
=======================================
  Coverage   99.69%   99.69%           
=======================================
  Files         275      276    +1     
  Lines       24170    24216   +46     
=======================================
+ Hits        24097    24143   +46     
  Misses         73       73           

Impacted Files	Coverage Δ
pennylane/measurements.py	100.00% <100.00%> (ø)
pennylane/ops/functions/__init__.py	100.00% <100.00%> (ø)
pennylane/ops/functions/map_wires.py	100.00% <100.00%> (ø)
pennylane/tape/tape.py	97.58% <100.00%> (ø)

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[AlbertMitjans]

[sc-27112]

[Jaybsoni]

Looks good to go for me 💯! Just a few small comments and failing tests to address then happy to approve

[albi3ro]

Left a couple of comments about switching references from QuantumTape to QuantumScript in the documentation.

But looks great! Glad to have this 🚀

[AlbertMitjans]

@Jaybsoni I will wait for your approval before merging

[Jaybsoni]

💯