Fix incorrect TeX

[kevinsung]

Summary

These bugs broke the internal docs build; see Qiskit/documentation#635.

Details and comments

• Incorrect omission of align environments.
• Underscores not escaped
• mbox not defined
• A few other issues

[qiskit-bot]

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

• @Cryoris
• @Qiskit/terra-core
• @ajavadia
• @ikkoham
• @nkanazawa1989

[coveralls]

Pull Request Test Coverage Report for Build 7613582066

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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.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.003%) to 89.508%

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Totals
Change from base Build 7584386082:	0.003%
Covered Lines:	59479
Relevant Lines:	66451

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💛 - Coveralls

[jakelishman]

Thanks for these fixes. My only question is about the inner environment choice - if the .. math:: already counts as a displaymode entry, then I'd expect the best environment inside it to be aligned, but if the backend wants the duplicated specification of displaymode, then fine.

[jakelishman]

0.45.2 is already released, so the milestone should have already been closed. We're not planning a 0.45.3 release, but assuming the documentation is decoupled from actual PyPI releases, we can still backport this to stable/0.45.

The CI failure was unrelated and fixed on main.

[Eric-Arellano]

We're not planning a 0.45.3 release, but assuming the documentation is decoupled from actual PyPI releases

Yep, we can build the docs from any CI artifact. So we only need it backported to stable/0.45.

[jakelishman]

Nice, thanks!