Fix typo in document qiskit.transpiler.preset_passmanagers.generate_preset_pass_manager.

[yoshida-ryuhei]

• I have added the tests to cover my changes.
  • no need
• I have updated the documentation accordingly.
• no need
• I have read the CONTRIBUTING document.

Summary

Fix a minor typo in the document for the qiskit.transpiler.preset_passmanagers.generate_preset_pass_manager.

Details and comments

The link in the document of qiskit.transpiler.preset_passmanagers.generate_preset_pass_manager is partially broken.
For the descriptions of layout_method in the parameters, the method DenseLayout has no link, as other methods have links.

This PR fixes the link.

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[coveralls]

Pull Request Test Coverage Report for Build 8228212457

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 33 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.04%) to 89.283%

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Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/expr.rs	1	93.81%
crates/qasm2/src/lex.rs	8	90.93%
crates/qasm2/src/parse.rs	24	96.23%

Totals
Change from base Build 8190588005:	-0.04%
Covered Lines:	59124
Relevant Lines:	66221

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💛 - Coveralls

[mtreinish]

LGTM, thanks for catching and fixing this.