remove Material Icons font to reduce deb package size.

pubspec.yaml

@@ -65,7 +65,7 @@ flutter:
   # The following line ensures that the Material Icons font is
   # included with your application, so that you can use the icons in
   # the material Icons class.
-  uses-material-design: true
+  uses-material-design: false
 
   # To add assets to your application, add an assets section, like this:
   assets: