Fix custom basis gates deprecation warning in generate_preset_pass_manager (backport #13460)

[mergify]

Summary

Small improvements on custom basis gates deprecation message for generate_preset_pass_manager:

• fixed missing space that lead to "providecustom" instead of "provide custom"
• replaced "custom" with "non-standard" and added an explicit mention to the gate that triggers the deprecation warning after @Cryoris getting the message triggered with ccp and not being able to pinpoint why (it's not custom, but also not standard).

Details and comments

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This is an automatic backport of pull request #13460 done by [Mergify](https://mergify.com).

[qiskit-bot]

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[coveralls]

Pull Request Test Coverage Report for Build 11934164028

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 11 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.008%) to 88.925%

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Files with Coverage Reduction	New Missed Lines	%
crates/accelerate/src/two_qubit_decompose.rs	1	92.12%
crates/qasm2/src/lex.rs	4	91.98%
crates/qasm2/src/parse.rs	6	97.62%

Totals
Change from base Build 11909933211:	-0.008%
Covered Lines:	79062
Relevant Lines:	88909

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💛 - Coveralls