Everywhere: Add sv suffix to strings relying on StringView(char const*)

Each of these strings would previously rely on StringView's char const*
constructor overload, which would call __builtin_strlen on the string.
Since we now have operator ""sv, we can replace these with much simpler
versions. This opens the door to being able to remove
StringView(char const*).

No functional changes.

Userland/Utilities/copy.cpp

@@ -24,7 +24,7 @@ struct Options {
 
 static Options parse_options(Main::Arguments arguments)
 {
-    char const* type = "text/plain";
+    auto type = "text/plain"sv;
     Vector<String> text;
     bool clear = false;