build: update cross-repo angular dependencies (21.1.x)

[angular-robot]

This PR contains the following updates:

Package	Type	Update	Change
@angular/ng-dev	devDependencies	digest	c018d7f → 15a2e18
angular/dev-infra	action	digest	eaf8b84 → 1d54555
devinfra	git_override	digest	eaf8b84 → 1d54555

🔡 If you wish to disable git hash updates, add ":disableDigestUpdates" to the extends array in your config.

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[alan-agius4]

This PR was merged into the repository. The changes were merged into the following branches:

• 21.1.x: fd7903c

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