doc formating issue in qiskit.pulse.library.Square_fun.rst (backport #13007)

[mergify]

Summary

There ar

e some formatting issues in https://docs.quantum.ibm.com/api/qiskit/qiskit.pulse.library.Square_fun.rst

Details and comments

With this PR, the doc looks like this:

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This is an automatic backport of pull request #13007 done by [Mergify](https://mergify.com).

[qiskit-bot]

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While you're waiting, please feel free to review other open PRs. While only a subset of people are authorized to approve pull requests for merging, everyone is encouraged to review open pull requests. Doing reviews helps reduce the burden on the core team and helps make the project's code better for everyone.

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• @Qiskit/terra-core
• @nkanazawa1989

[coveralls]

Pull Request Test Coverage Report for Build 10493655537

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.04%) to 89.847%

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Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/lex.rs	2	93.23%

Totals
Change from base Build 10491461200:	0.04%
Covered Lines:	66833
Relevant Lines:	74385

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💛 - Coveralls