LibWeb: Make Default.css clearer about the style of input elements

Previously, all input elements were given a textbox-like style by
default, this was then undone by another CSS rule in the case of certain
types of input element. This commit makes it so that the first rule
simply ignores those types instead.

Co-authored-by: Sam Atkins <atkinssj@serenityos.org>

Userland/Libraries/LibWeb/CSS/Default.css

@@ -26,7 +26,7 @@ label {
 }
 
 /* FIXME: This is a temporary hack until we can render a native-looking frame for these. */
-input, textarea {
+input:not([type=submit], input[type=button], input[type=reset], input[type=checkbox], input[type=radio]), textarea {
     border: 1px solid ButtonBorder;
     min-width: 80px;
     min-height: 16px;
@@ -44,14 +44,6 @@ textarea {
     height: attr(rows lh, 2lh);
 }
 
-input[type=submit], input[type=button], input[type=reset], input[type=checkbox], input[type=radio] {
-    border: none;
-    min-width: unset;
-    min-height: unset;
-    width: unset;
-    cursor: unset;
-}
-
 input::placeholder {
     color: GrayText;
 }