[Ionic 4] Style ion-button line-height in shadow DOM

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<ion-button expand="block" fill="outline" class="add-line-height" >A Mental Health<br> Professional <br> 1 (800) 667-8888</ion-button>

ion-button.add-line-height{
*{
line-height: 1.5;
}
}

ion-button-;ine-height419×565 24.9 KB