Remove deprecated stochastic swap transpiler pass

[mtreinish]

Summary

This commit removes the stochastic swap transpiler pass and its associated routing stage plugin. This pass has been superseded by sabre at this point and it was deprecated in the Qiskit 1.3.0 release.

Details and comments

Part of #13699

[qiskit-bot]

One or more of the following people are relevant to this code:

• @Qiskit/terra-core

[coveralls]

Pull Request Test Coverage Report for Build 13511266405

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 25 unchanged lines in 6 files lost coverage.
• Overall coverage decreased (-0.02%) to 87.973%

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Files with Coverage Reduction	New Missed Lines	%
crates/accelerate/src/unitary_synthesis.rs	1	94.39%
qiskit/transpiler/passes/layout/dense_layout.py	1	95.12%
qiskit/transpiler/preset_passmanagers/builtin_plugins.py	1	95.5%
crates/qasm2/src/lex.rs	3	92.48%
crates/circuit/src/dag_circuit.rs	9	86.13%
qiskit/transpiler/passes/routing/utils.py	10	0.0%

Totals
Change from base Build 13508932591:	-0.02%
Covered Lines:	77502
Relevant Lines:	88097

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💛 - Coveralls

[jakelishman]

o7 to the first Rust code of Qiskit

[jakelishman]

Oh also I meant to write in the top review comment: we need to update the qiskit.transpiler and qiskit.transpiler.preset_passmanager.plugin docstrings to remove the reference to the stochastic plugin.

[jakelishman]

There's also a couple of places in the benchmark suite that refer to the stochastic plugin.

[mtreinish]

There's also a couple of places in the benchmark suite that refer to the stochastic plugin.

Fixed in: b057980

Oh also I meant to write in the top review comment: we need to update the qiskit.transpiler and qiskit.transpiler.preset_passmanager.plugin docstrings to remove the reference to the stochastic plugin.

Fixed in cdf7826

I opted to keep the reference I found in plugin.py because it looked like the only mention there was that "stochastic" was marking it as a reserved which seems fine to keep just so people don't have issues if they want to develop a plugin that supports 1.x and 2.x.

[jakelishman]

I can live with leaving stochastic in the "reserved names" list, though it wouldn't surprise me if there's a PR in 6 months' time deleting it, confused about why we're reserving something we don't use haha.

[jakelishman]

Oh, a lint complaint about import warnings in test/python/transpiler/test_mappers.py.