Remove Pulse library URL renaming in docs (backport #13107)

[mergify]

The workaround from #9748 is no longer necessary because there is no conflict with capitalization. So, we can go back to using the default URL for these classes, such as qiskit.pulse.library.Constant.

We will set up redirects in docs.quantum.ibm.com for this URL change.

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This is an automatic backport of pull request #13107 done by Mergify.

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[coveralls]

Pull Request Test Coverage Report for Build 10814237148

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 4 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.01%) to 89.753%

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Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/lex.rs	4	91.23%

Totals
Change from base Build 10814134368:	0.01%
Covered Lines:	66871
Relevant Lines:	74506

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💛 - Coveralls