Port project file tests to use insta

src/snapshot_middleware/snapshots/test__project_from_folder.snap

@@ -0,0 +1,14 @@
+---
+source: src/snapshot_middleware/project.rs
+expression: instance_snapshot
+---
+snapshot_id: ~
+metadata:
+  ignore_unknown_instances: true
+  contributing_paths:
+    - /foo/default.project.json
+  project_node: ~
+name: indirect-project
+class_name: Folder
+properties: {}
+children: []