fix(@schematics/angular): drop composite in tsconfig

[cexbrayat]

PR Checklist

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• The commit message follows our guidelines: https://github.com/angular/angular-cli/blob/main/CONTRIBUTING.md#-commit-message-guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

What is the current behavior?

Based on this TS discussion, composite is in fact not necessary, the TS docs are just misleading.

What is the new behavior?

This removes composite from the configs, as it was recently done in create-vue (see vuejs/create-vue#635).

Does this PR introduce a breaking change?

• Yes
• No

Other information