Update dependency webpack to v5.21.0

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
webpack	5.20.2 -> 5.21.0

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Release Notes

webpack/webpack

v5.21.0

Compare Source

Features

• add __webpack_base_uri__ to change base URI at runtime
• add stats.errorDetails: "auto" to show error details automatically when there are only 1 or 2 errors

Bugfixes

• fix a hanging build when using the persistent cache without a package.json in cwd

Developer Experience

• add typings for the stats JSON
• change default for stats.errorDetails to "auto" when using toString
• Highlight important text in error message with colors
  • e. g. Did you mean ...? and similar hints are shown in green

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