Update dependency preload-webpack-plugin to v3.0.0-beta.4

[renovate-bot]

This PR contains the following updates:

Package	Type	Update	Change
preload-webpack-plugin	devDependencies	patch	3.0.0-beta.3 -> 3.0.0-beta.4

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Release Notes

googlechromelabs/preload-webpack-plugin

v3.0.0-beta.4

Compare Source

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