I am trying to limit the file type to CSV in the `ng-file-upload` component but it isn't working - it still accepts all files.

I have tried both `ngf-pattern="'*.csv'"` and `ngf-pattern="*.csv"`.

Code:

```
   <button class="btn btn-info" type="file" ngf-select="uploadFiles($file, $invalidFiles)"
                        ngf-pattern="'*.csv'" ngf-max-height="1000" ngf-max-size="1MB">
                    <i class="fa fa-upload"></i> {{'main.users.import.button' |translate}} </button>

```

Dependency:

```
  "ng-file-upload": "~10.0.2",

```