Fix TwoLocal example: use compose instead of + (backport #12609)

[mergify]

Summary

Fixes #12590.

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This is an automatic backport of pull request #12609 done by [Mergify](https://mergify.com).

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[coveralls]

Pull Request Test Coverage Report for Build 9595283940

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 10 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.003%) to 89.961%

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Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/lex.rs	4	93.13%
crates/qasm2/src/parse.rs	6	97.61%

Totals
Change from base Build 9564656449:	0.003%
Covered Lines:	61831
Relevant Lines:	68731

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💛 - Coveralls