fix(app): little fixes on style

tests/ui/modules/Linphone/Colors.qml

@@ -19,4 +19,7 @@ QtObject {
 
   property string k: '#FFFFFF' // Text color.
   property string l: '#000000' // Text color.
+
+  property string m: '#D1D1D1' // SmallButton Normal.
+  property string n: '#C0C0C0' // SmallButton Hovered.
 }

tests/ui/modules/Linphone/Styles/Form/ExclusiveButtonsStyle.qml

@@ -8,10 +8,10 @@ QtObject {
 
   property QtObject button: QtObject {
     property QtObject color: QtObject {
-      property string hovered: '#C0C0C0'
-      property string normal: '#D1D1D1'
-      property string pressed: '#FE5E00'
-      property string selected: '#8E8E8E'
+      property string hovered: Colors.n
+      property string normal: Colors.m
+      property string pressed: Colors.i
+      property string selected: Colors.g
     }
   }
 }

tests/ui/modules/Linphone/Styles/Form/SmallButtonStyle.qml

@@ -9,15 +9,15 @@ QtObject {
     property int radius: 10
 
     property QtObject color: QtObject {
-      property string hovered: '#C0C0C0'
-      property string normal: '#D1D1D1'
-      property string pressed: '#FE5E00'
+      property string hovered: Colors.n
+      property string normal: Colors.m
+      property string pressed: Colors.i
     }
   }
 
   property QtObject text: QtObject {
     property int fontSize: 8
 
-    property string color: '#FFFFFF'
+    property string color: Colors.k
   }
 }