Support ESLint v10

[azat-io]

Summary

• Replace deprecated context.getSourceCode() with context.sourceCode fallback for ESLint v10 compatibility
• Remove type property from test error assertions (removed in ESLint v10 RuleTester)
• Update eslint devDependency to ^10.0.0

Backward compatibility with ESLint v9 is preserved via fallbacks.

[github-actions]

Package Changes Through 6a5ba09

There are 1 changes which include eslint-plugin-prefer-let with minor

Planned Package Versions

The following package releases are the planned based on the context of changes in this pull request.

package	current	next
eslint-plugin-prefer-let	4.0.1	4.1.0

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[ai]

I need this PR too