reduce memory usage in analyser (#8061)

### Description


* reduce JSValue size by 40 bytes (from 88 bytes)

### Testing Instructions

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Closes PACK-3029

crates/turbopack-ecmascript/src/analyzer/mod.rs

@@ -370,7 +370,7 @@ pub enum JsValue {
  /// A constant primitive value.
  Constant(ConstantValue),
  /// An constant URL object.
- Url(Url),
+ Url(Box<Url>),
  /// Some kind of well-known object
  /// (must not be an array, otherwise Array.concat needs to be changed)
  WellKnownObject(WellKnownObjectKind),

crates/turbopack-ecmascript/src/analyzer/well_known.rs

@@ -478,6 +478,7 @@ pub fn path_to_file_url(args: Vec<JsValue>) -> JsValue {
  if args.len() == 1 {
  if let Some(path) = args[0].as_str() {
  Url::from_file_path(path)
+ .map(Box::new)
  .map(JsValue::Url)
  .unwrap_or_else(|_| {
  JsValue::unknown(