chore: normalize variant size for scoped_file_system::Entry

```
warning: large size difference between variants
  --> src/addon/file_server/scoped_file_system.rs:35:5
   |
35 |     File(File),
   |     ^^^^^^^^^^ this variant is 304 bytes
   |
   = note: `#[warn(clippy::large_enum_variant)]` on by default
note: and the second-largest variant is 24 bytes:
  --> src/addon/file_server/scoped_file_system.rs:36:5
   |
36 |     Directory(Directory),
   |     ^^^^^^^^^^^^^^^^^^^^
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#large_enum_variant
help: consider boxing the large fields to reduce the total size of the enum
   |
35 |     File(Box<File>),
   |          ~~~~~~~~~
```

Author: LeoBorai

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "http-server"
-version = "0.5.4"
+version = "0.5.7"
 authors = ["Esteban Borai <estebanborai@gmail.com>"]
 edition = "2018"
 description = "Simple and configurable command-line HTTP server"
@@ -40,7 +40,7 @@ handlebars = "4.1.4"
 hyper = { version = "0.14.14", features = ["http1", "server", "stream", "tcp"] }
 local-ip-address = "0.4.4"
 mime_guess = "2.0.3"
-rustls = "0.20.1"
+rustls = "0.20.2"
 rustls-pemfile = "0.2.1"
 tokio = { version = "1.13.0", features = ["fs", "rt-multi-thread", "signal", "macros"] }
 tokio-rustls = "0.23.1"

Cargo.toml

@@ -104,7 +104,7 @@ impl<'a> FileServer {
             Ok(entry) => match entry {
                 Entry::Directory(dir) => self.render_directory_index(dir.path()).await,
                 Entry::File(file) => {
-                    make_http_file_response(file, CacheControlDirective::MaxAge(2500)).await
+                    make_http_file_response(*file, CacheControlDirective::MaxAge(2500)).await
                 }
             },
             Err(err) => match err.kind() {

src/addon/file_server/mod.rs

@@ -32,7 +32,7 @@ impl Directory {
 /// `ScopedFileSystem`
 #[derive(Debug)]
 pub enum Entry {
-    File(File),
+    File(Box<File>),
     Directory(Directory),
 }
 
@@ -109,7 +109,7 @@ impl ScopedFileSystem {
             return Ok(Entry::Directory(Directory { path: entry_path }));
         }
 
-        Ok(Entry::File(File::new(entry_path, file, metadata)))
+        Ok(Entry::File(Box::new(File::new(entry_path, file, metadata))))
     }
 }