Removed code deprecated in 0.20

[Raghav-Bell]

It fixes #10747

Summary

Details and comments

Please add Changelog: Removal tag.

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[Raghav-Bell]

In qiskit/visualization/circuit/latex.py:52 (__init__) there is no argument gregs, i think it should be qregs i,e removed qregs.

[Raghav-Bell]

tox -epy310 -- -n test\python\visualization\test_circuit_latex.py it doesn't run due to absent of pylatexenc even though it is installed in the env.

[1ucian0]

Thanks! While I check for the rest of the code, do not forget to add the release note:

create a release note in the category upgrade:. If you can include an example with an alternative for user to migrate to the new code, as this change might break users code.

[1ucian0]

Here some suggestions on how to reformulate the release notes. Let me know what you think.

[1ucian0]

Suggested change

	Code and tests deprecated in 0.20 are removed.
	:class:`.visualization.QCircuitImage` objects no longer supports
	`qregs`, `cregs`, `layout`and `global_phase` arguments.
	The class constructor arguments `qregs`, `cregs`, `layout`and `global_phase` for :class:`.visualization.QCircuitImage` are removed, as they were deprecated in 0.20.

[1ucian0]

:meth:`~subgraph`

wont resolve, as it is being removed. By this PR :)

Suggested change

	Code and tests deprecated in 0.20 are removed. In
	:class:`.transpiler.CouplingMap` :meth:`~subgraph` is removed.
	:meth:`~reduce` can be used in place of
	:meth:`~subgraph`.
	The method `subgraph` in :class:`.transpiler.CouplingMap`
	is being removed as it was deprecated in 0.20. The method
	:meth:`~reduce` can be used in its place. It does the same thing, but preserves nodelist order.

[1ucian0]

No need for this one, since it is a private method.

Suggested change

	- |
	Code and tests deprecated in 0.20 are removed. In
	:class:`.dagcircuit.DAGCircuit` private :meth:`~_copy_circuit_metadata` is removed.
	Instead use public :meth:`~copy_empty_like` with same functionality.

[1ucian0]

Suggested change

	Code and tests deprecated in 0.20 are removed. In
	:class:`.synthesis.SuzukiTrotter` deprecation warning for
	odd `order` is replaced with `ValueError`.
	Refer to `#10747 <https://github.com/Qiskit/qiskit/issues/10747>`
	The parameter `order` in :class:`.synthesis.SuzukiTrotter` raises an exception instead of deprecation warning when set in an odd number. Suzuki product formulae are symmetric and therefore only defined for even orders.

[Raghav-Bell]

Hmm, your suggestions are quite good, i have tried to accommodate them in the commit. Thanks

[1ucian0]

Great work! Let's get it merged once you solve the conflicts in qiskit/dagcircuit/dagcircuit.py

release note comments addressed

[coveralls]

Pull Request Test Coverage Report for Build 6149701107

• 3 of 4 (75.0%) changed or added relevant lines in 2 files are covered.
• 3 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.02%) to 87.311%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
qiskit/synthesis/evolution/suzuki_trotter.py	1	2	50.0%

Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/lex.rs	3	91.67%

Totals
Change from base Build 6124202354:	0.02%
Covered Lines:	74469
Relevant Lines:	85292

---

💛 - Coveralls

[1ucian0]

LGTM, Thanks!