chore: Update ng-schemactics README (#9269)
chore: Update ng-schemactics README (#9269)

**What kind of change does this PR introduce?**

Updates the README for `@puppeteer/ng-schematics` with better
information. Fixes broken command
puppeteer/puppeteer,puppeteer/puppeteer,puppeteer/puppeteer,puppeteer/puppeteer