Fix flipping of gate direction in transpiler for CZ gate

[peendebak]

Summary

Fixes #8387.

Details and comments

The CZ gate is symmetric, so should not fail in a pass that flips gates to match the coupling map.

Implementation based on code by @JMuff22

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[coveralls]

Pull Request Test Coverage Report for Build 3104955084

• 8 of 13 (61.54%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.004%) to 84.403%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
qiskit/transpiler/passes/utils/gate_direction.py	8	13	61.54%

Totals
Change from base Build 3102513100:	-0.004%
Covered Lines:	59270
Relevant Lines:	70223

---

💛 - Coveralls

[mtreinish]

Overall the code LGTM, but before we merge do you mind adding a fixes relaese note to document the the bugfix. The process for doing that is documented here: https://github.com/Qiskit/qiskit-terra/blob/main/CONTRIBUTING.md#release-notes

[peendebak]

Overall the code LGTM, but before we merge do you mind adding a fixes relaese note to document the the bugfix. The process for doing that is documented here: https://github.com/Qiskit/qiskit-terra/blob/main/CONTRIBUTING.md#release-notes

@mtreinish Release notes have been added.

[mtreinish]

LGTM, thanks for adding the release note

[mtreinish]

Suggested change

	Fix a problem in the `GateDirection` transpiler pass for the CZ gate. The CZ is symmetric, so flipping the qubit arguments is allowed to match the directed coupling map.
	Fixed an issue in the :class:`~.GateDirection` transpiler pass for circuits with :class:`~.CZGate. The CZ gate is symmetric, so flipping the qubit arguments is allowed to match the directed coupling map.