Remove qiskit.quantum_info.synthesis for Qiskit 1.0 release

[ShellyGarion]

Summary

Remove qiskit.quantum_info.synthesis that has been deprecated in #11460

Details and comments

[qiskit-bot]

One or more of the the following people are requested to review this:

• @Cryoris
• @Qiskit/terra-core
• @ajavadia
• @ikkoham
• @levbishop

[coveralls]

Pull Request Test Coverage Report for Build 7692402441

Warning: This coverage report may be inaccurate.

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A quick fix for this PR: rebase it; your next report should be accurate.

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 71 unchanged lines in 7 files lost coverage.
• Overall coverage increased (+0.005%) to 89.54%

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Files with Coverage Reduction	New Missed Lines	%
qiskit/primitives/containers/bindings_array.py	1	92.59%
qiskit/transpiler/passes/optimization/commutative_inverse_cancellation.py	2	96.92%
crates/qasm2/src/lex.rs	3	92.44%
qiskit/circuit/gate.py	7	90.91%
qiskit/quantum_info/operators/operator.py	14	94.94%
qiskit/quantum_info/operators/predicates.py	16	64.36%
qiskit/circuit/quantumcircuit.py	28	94.36%

Totals
Change from base Build 7645403491:	0.005%
Covered Lines:	59545
Relevant Lines:	66501

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💛 - Coveralls

[ElePT]

The removal looks good, and I believe that we can already remove the on hold tag, right? Now that #11460 has been merged.