fix: filter deleted assets in processAdditionalAssets hook

[xiaoxiaojx]

What kind of change does this PR introduce?
Fixes webpack/compression-webpack-plugin#390

The original commit that fixed the issue is d2d34e6. This PR is only for fixing lint issues and verifying test case execution.

Did you add tests for your changes?
No
Does this PR introduce a breaking change?
No
What needs to be documented once your changes are merged?
No

[codspeed-hq]

CodSpeed Performance Report

Merging #19751 will improve performances by 58.43%

_{Comparing fix/lint_processAdditionalAssets (953d2cc) with main (d2d34e6)}

Summary

⚡ 4 improvements
✅ 38 untouched benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	benchmark "devtool-source-map", scenario '{"name":"mode-development-rebuild","mode":"development","watch":true}'	114.5 ms	79.5 ms	+44.12%
⚡	benchmark "many-chunks-commonjs", scenario '{"name":"mode-development-rebuild","mode":"development","watch":true}'	124.4 ms	92.6 ms	+34.39%
⚡	benchmark "many-chunks-esm", scenario '{"name":"mode-development-rebuild","mode":"development","watch":true}'	145.7 ms	98.1 ms	+48.53%
⚡	benchmark "three-long", scenario '{"name":"mode-development-rebuild","mode":"development","watch":true}'	351.1 ms	221.6 ms	+58.43%

[alexander-akait]

Thank you ❤️