build: Remove dependency overwrite for ffi

pubspec.lock

@@ -394,7 +394,7 @@ packages:
     source: hosted
     version: "1.3.1"
   ffi:
-    dependency: "direct overridden"
+    dependency: transitive
     description:
       name: ffi
       sha256: a38574032c5f1dd06c4aee541789906c12ccaab8ba01446e800d9c5b79c4a978

pubspec.yaml

@@ -143,8 +143,6 @@ msix_config:
   install_certificate: false
 
 dependency_overrides:
-  # Until all dependencies are compatible. Missing: flutter_matrix_html
-  ffi: ^2.0.0
   # fake secure storage plugin for Windows
   # See: https://gitlab.com/gitlab-com/gl-infra/reliability/-/issues/15161
   flutter_matrix_html: