LibJS: Use new format functions everywhere

This changes the remaining uses of the following functions across LibJS:

- String::format() => String::formatted()
- dbg() => dbgln()
- printf() => out(), outln()
- fprintf() => warnln()

I also removed the relevant 'LogStream& operator<<' overloads as they're
not needed anymore.

Libraries/LibJS/CMakeLists.txt

@@ -55,7 +55,6 @@ set(SOURCES
     Runtime/Object.cpp
     Runtime/ObjectPrototype.cpp
     Runtime/PrimitiveString.cpp
-    Runtime/PropertyAttributes.cpp
     Runtime/ProxyConstructor.cpp
     Runtime/ProxyObject.cpp
     Runtime/Reference.cpp