--no-livereload not working

**Description:**

Adding the `--no-livereload` flag to `ionic serve` doesn't seem to do anything.

**Steps to Reproduce:**

- run `ionic serve --no-livereload`
- save a file and watch the browser automatically reload

**My `ionic info`:**

```
Ionic:

Ionic CLI : 6.0.2 (/usr/local/lib/node_modules/@ionic/cli)
Ionic Framework : @ionic/angular 5.0.0
@angular-devkit/build-angular : 0.801.3
@angular-devkit/schematics : 8.1.3
@angular/cli : 8.1.3
@ionic/angular-toolkit : 2.1.2

Capacitor:

Capacitor CLI : 1.5.0
@capacitor/core : 1.5.0

Utility:

cordova-res : not installed
native-run : not installed

System:

NodeJS : v12.14.1 (/usr/local/bin/node)
npm : 6.13.4
OS : macOS Catalina
```

**Other Information:**

I'm using Firefox 72.0.2 if it makes a difference...

Start at the `ionic serve` command and reproduce the behavior with `ionic serve --no-livereload`, then save a file while watching the browser. Trace how the flag is handled and confirm the fix by verifying that the browser no longer reloads automatically.

Rédigé par le modèle d'indexation à partir du texte de l'issue.