Everywhere: Use LibFileSystem where trivial

Author: https://github.com/cammo1123
Commit: 1d24f394c6
Pull-request: https://github.com/SerenityOS/serenity/pull/17789
Reviewed-by: https://github.com/AtkinsSJ
Reviewed-by: https://github.com/caoimhebyrne
Reviewed-by: https://github.com/kleinesfilmroellchen ✅
Reviewed-by: https://github.com/linusg
Reviewed-by: https://github.com/pascalpuffke
Reviewed-by: https://github.com/timschumi ✅

Userland/Services/WebContent/main.cpp

@@ -5,11 +5,11 @@
  */
 
 #include "ImageCodecPluginSerenity.h"
-#include <LibCore/DeprecatedFile.h>
 #include <LibCore/EventLoop.h>
 #include <LibCore/LocalServer.h>
 #include <LibCore/StandardPaths.h>
 #include <LibCore/System.h>
+#include <LibFileSystem/FileSystem.h>
 #include <LibIPC/SingleServer.h>
 #include <LibMain/Main.h>
 #include <LibWeb/Bindings/MainThreadVM.h>
@@ -29,7 +29,7 @@ ErrorOr<int> serenity_main(Main::Arguments)
 
     // This must be first; we can't check if /tmp/webdriver exists once we've unveiled other paths.
     auto webdriver_socket_path = DeprecatedString::formatted("{}/webdriver", TRY(Core::StandardPaths::runtime_directory()));
-    if (Core::DeprecatedFile::exists(webdriver_socket_path))
+    if (FileSystem::exists(webdriver_socket_path))
         TRY(Core::System::unveil(webdriver_socket_path, "rw"sv));
 
     TRY(Core::System::unveil("/res", "r"));