Fix the font for searchbars being styled correctly

By setting the font.italic to true, we actually reset the entire font.

Fixes #12565

resources/qml/SearchBar.qml

@@ -15,7 +15,7 @@ Cura.TextField
     leftPadding: searchIcon.width + UM.Theme.getSize("default_margin").width * 2
 
     placeholderText: catalog.i18nc("@placeholder", "Search")
-    font.italic: true
+    font: UM.Theme.getFont("default_italic")
 
     UM.ColorImage
     {

resources/qml/Settings/SettingView.qml

@@ -46,7 +46,7 @@ Item
             topPadding: height / 4
             leftPadding: searchIcon.width + UM.Theme.getSize("default_margin").width * 2
             placeholderText: catalog.i18nc("@label:textbox", "Search settings")
-            font.italic: true
+            font: UM.Theme.getFont("default_italic")
 
             property var expandedCategories
             property bool lastFindingSettings: false