fix(js_analyzer): binary expression utils

[Sec-ant]

Summary

This PR fixes an issue where an operator with no spaces around in a binary expression can break the js analyzer. Specifically when rule lint/suspicious/noMisrefactoredShorthandAssign is enabled.

Closes #2243

Test Plan

Added a test case.

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Lighthouse	1 paths audited Performance: 99 (no change from production) Accessibility: 97 (no change from production) Best Practices: 100 (no change from production) SEO: 93 (no change from production) PWA: - View the detailed breakdown and full score reports

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[codspeed-hq]

CodSpeed Performance Report

Merging #2250 will degrade performances by 18.81%

_{⚠️ No base runs were found}

_{Falling back to comparing Sec-ant:fix/js-analyzer-binary-expression-utils (46c963b) with main (d98c549)}

Summary

⚡ 1 improvements
❌ 1 regressions
✅ 91 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	Sec-ant:fix/js-analyzer-binary-expression-utils	Change
❌	big5-added.json[uncached]	2.7 ms	3.4 ms	-18.81%
⚡	db.json[uncached]	87.1 ms	79.7 ms	+9.22%