after changing ionic.config.json the file is not refreshed

**Description:**

after using ionic serve the ionic.config.json is not being refreshed. I have set these values in the file
{
"name": "MyIonicProject",
"app_id": "",
"type": "ionic-angular",
"integrations": {
"cordova": {}
},
"proxies": [{
"path": "/data/",
"proxyUrl": "http://localhost/data/"
},{
"path": "/login/",
"proxyUrl": "http://api.fcmsoft.com/account/"
}]
}

but /login/ is not being changed it keeps remembering the old path in the proxyUrl.

**My `ionic info`:**

```
cli packages: (C:\Users\themhz\AppData\Roaming\npm\node_modules)

@ionic/cli-utils : 1.19.2
ionic (Ionic CLI) : 3.20.0

global packages:

cordova (Cordova CLI) : not installed

local packages:

@ionic/app-scripts : 3.1.8
Cordova Platforms : ios 4.5.4
Ionic Framework : ionic-angular 3.9.2

System:

Node : v8.9.1
npm : 6.0.0-next.0
OS : Windows 10

Environment Variables:

ANDROID_HOME : not set

Misc:

backend : pro
```

**Other Information:**

Start by reproducing the issue with the repository's ionic serve entry point and an edited ionic.config.json containing the /login/ proxy. Trace how ionic serve loads or caches the proxy configuration, then verify that changing proxyUrl is reflected without retaining the old path.

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