chore(deps): update dependency @angular-builders/custom-webpack to v21

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
@angular-builders/custom-webpack (source)	20.0.0 → 21.0.3

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Release Notes

just-jeb/angular-builders (@​angular-builders/custom-webpack)

v21.0.3

Compare Source

Note: Version bump only for package @​angular-builders/custom-webpack

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Configuration

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• Automerge
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🚦 Automerge: Enabled.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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This PR was generated by Mend Renovate. View the repository job log.

[renovate]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
• you rename this PR's title to start with "rebase!" to trigger it manually

The artifact failure details are included below:

File name: packages/examples/angular-webpack-example/package-lock.json

npm ERR! code ERESOLVE
npm ERR! ERESOLVE unable to resolve dependency tree
npm ERR! 
npm ERR! While resolving: angular-webpack-example@0.0.0
npm ERR! Found: @angular/compiler-cli@20.3.14
npm ERR! node_modules/@angular/compiler-cli
npm ERR!   dev @angular/compiler-cli@"20.3.14" from the root project
npm ERR! 
npm ERR! Could not resolve dependency:
npm ERR! peer @angular/compiler-cli@"^21.0.0" from @angular-builders/custom-webpack@21.0.3
npm ERR! node_modules/@angular-builders/custom-webpack
npm ERR!   dev @angular-builders/custom-webpack@"21.0.3" from the root project
npm ERR! 
npm ERR! Fix the upstream dependency conflict, or retry
npm ERR! this command with --force, or --legacy-peer-deps
npm ERR! to accept an incorrect (and potentially broken) dependency resolution.
npm ERR! 
npm ERR! See /runner/cache/others/npm/eresolve-report.txt for a full report.

npm ERR! A complete log of this run can be found in:
npm ERR!     /runner/cache/others/npm/_logs/2026-04-16T02_05_03_577Z-debug-0.log