LibGUI: Give some widgets a reasonable default fixed height

Instead of hard-coding 22 in random places, just make the following
widgets have a fixed height of 22 by default: Button, CheckBox,
ColorInput, ComboBox, RadioButton, SpinBox, TextBox.

In the future we can make this relative to the current font size,
but for now at least this centralizes the setting a bit better.

Libraries/LibGUI/TextBox.cpp

@@ -31,6 +31,7 @@ namespace GUI {
 TextBox::TextBox()
     : TextEditor(TextEditor::SingleLine)
 {
+    set_fixed_height(22);
 }
 
 TextBox::~TextBox()