Add MCRX, MCRY and MCRZ gates to the circuit library

[king-p3nguin]

Summary

Resolve #12048

Details and comments

• We may need to change the logic of _mcsu2_real_diagonal for Controlled UGate with a parameterized angle fails with 4 or more controls #12135 (maybe in other PR)
• Deprecate importing mcrx, mcry and mcrz from qiskit/circuit/library/standard_gates/multi_control_rotation_gates.py

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[coveralls]

Pull Request Test Coverage Report for Build 9011841055

Details

• 322 of 352 (91.48%) changed or added relevant lines in 7 files are covered.
• 14 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.004%) to 89.623%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
qiskit/circuit/library/standard_gates/ry.py	79	80	98.75%
qiskit/circuit/library/standard_gates/rx.py	135	142	95.07%
qiskit/circuit/library/standard_gates/multi_control_rotation_gates.py	0	8	0.0%
qiskit/circuit/quantumcircuit.py	54	68	79.41%

Files with Coverage Reduction	New Missed Lines	%
qiskit/transpiler/passes/synthesis/unitary_synthesis.py	3	88.02%
crates/qasm2/src/lex.rs	5	92.88%
qiskit/circuit/library/standard_gates/multi_control_rotation_gates.py	6	0.0%

Totals
Change from base Build 9004289325:	-0.004%
Covered Lines:	62323
Relevant Lines:	69539

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💛 - Coveralls

[ShellyGarion]

Thanks for your contribution @king-p3nguin.
I have a few preliminary questions and comments.

1. I don't understand why there are so many new classes.
   MCRXGate, MCRXPUCXBasis, MCRYGate, MCRYPUCXBasis, MCRYVChain, MCRZGate, MCRZPUCXBasis ?
   Isn't it enough to have one class for each rotation direction? see the code of MCPhaseGate.

2. There are several copypasting misprints in the classes docstrings that are a bit confusing.

3. I'm not sure if the imports through qiskit/circuit/library/standard_gates/multi_control_rotation_gates.py should be deprecated, since the way that these are used today are via QuantumCircuit.mcrx, QuantumCircuit.mcry and QuantumCircuit.mcrz .

4. Instead of changing the logic of _mcsu2_real_diagonal to solve Controlled UGate with a parameterized angle fails with 4 or more controls #12135, perhaps you can handle the two cases of ParameterValueType and float separately as a preliminary solution?
   see the code of MCPhaseGate.