fix(minifier): inline single-use vars past non-computed object keys

[ulrichstark]

Fixes #20802

This fixes a bug in single-use variable inlining where object literals with non-computed string keys like "-a" were incorrectly treated like computed properties and stopped further substitution.

[codspeed-hq]

Merging this PR will not alter performance

✅ 44 untouched benchmarks
⏩ 12 skipped benchmarks¹

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_{Comparing ulrichstark:fix(minifier)--inline-single-use-vars-past-non-computed-object-keys (c333546) with main (6624513)²}

Footnotes

1. 12 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

2. No successful run was found on main (6171217) during the generation of this report, so 6624513 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩