fix unit tests no longer in separate package

Author: vkovec

TestProjects/FbxTests/Packages/manifest.json

@@ -42,6 +42,6 @@
   },
   "registry": "https://staging-packages.unity.com",
   "testables": [
-    "com.unity.formats.fbx.tests"
+    "com.unity.formats.fbx"
   ]
 }

com.unity.formats.fbx/Tests/Scripts/ExporterTestBaseAPI.cs

@@ -13,7 +13,7 @@ public abstract class ExporterTestBaseAPI
         /// Use this path if you want to load some data for testing, e.g. a
         /// material or scene or fbx.
         /// </summary>
-        public const string PathToTestData = "Packages/com.unity.formats.fbx.tests/Tests";
+        public const string PathToTestData = "Packages/com.unity.formats.fbx/Tests";
 
         /// <summary>
         /// Sleep an amount of time (in ms) so we can safely assume that the