Fix CommutationChecker for comparison with rotation gates on angles $k\pi$

[Cryoris]

Summary

In #13302 a mistake creeped in, accidentally stating that rotation gates commute for angles that are multiples of $\pi$ instead of $2\pi$. I would've expected this to break somewhere in the test suite, now explicit tests are added. No reno as this is not yet released.

[qiskit-bot]

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

• @Qiskit/terra-core

[mtreinish]

Good catch, I'm surprised we didn't hit this anywhere during review of the PR. But good to catch this now.

[coveralls]

Pull Request Test Coverage Report for Build 11692110509

Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• 32 unchanged lines in 6 files lost coverage.
• Overall coverage decreased (-0.04%) to 88.761%

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Files with Coverage Reduction	New Missed Lines	%
crates/accelerate/src/unitary_synthesis.rs	1	92.2%
crates/accelerate/src/two_qubit_decompose.rs	1	92.09%
qiskit/transpiler/passes/synthesis/unitary_synthesis.py	2	58.05%
crates/qasm2/src/lex.rs	3	91.98%
qiskit/synthesis/two_qubit/xx_decompose/decomposer.py	7	90.77%
crates/qasm2/src/parse.rs	18	95.77%

Totals
Change from base Build 11690680453:	-0.04%
Covered Lines:	77026
Relevant Lines:	86779

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💛 - Coveralls