message: docs: update update guide to use `ng update` instead of `npm i`
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diff: @@ -7,12 +7,14 @@ This guide contains everything you need to know about updating to the next Angul
  If your application uses the CLI, you can update to version 9 automatically with the help of the `ng update` script:
  ```
  -npm install --no-save @angular/cli@^8.3.15
  +ng update @angular/core@8 @angular/cli@8
  +git add .
  +git commit --all -m "build: update Angular packages to latest 8.x version"
  ng update @angular/cli @angular/core --next
  ```
  <div class="alert is-important">
  -In order to improve the updating experience, we strongly suggest that you update your local `@angular/cli` to version 8.3.15 or later 8.x version before updating.
  +In order to improve the updating experience, we strongly suggest that you update to the latest 8.x version of `@angular/core` and `@angular/cli`.
  Additionally, during the RC period, the `--next` command line flag is required. This flag will no longer be necessary once version 9 final is released.
  </div>
  