feat(virtual test-support.js): fix the checks in module-resolver

packages/core/src/module-resolver.ts

@@ -437,14 +437,10 @@ export class Resolver {
     let pkg = this.packageCache.ownerOfFile(request.fromFile);
     if (pkg?.root !== this.options.engines[0].root) {
       throw new Error(
-        `bug: found an import of ${request.specifier} in ${request.fromFile}, but this is not the top-level Ember app. The top-level Ember app is the only one that has support for @embroider/core/vendor. If you think something should be fixed in Embroider, please open an issue on https://github.com/embroider-build/embroider/issues.`
+        `bug: found an import of ${request.specifier} in ${request.fromFile}, but this is not the top-level Ember app. The top-level Ember app is the only one that has support for @embroider/core/test-support.js. If you think something should be fixed in Embroider, please open an issue on https://github.com/embroider-build/embroider/issues.`
       );
     }
 
-    if (!pkg?.isV2Ember()) {
-      throw new Error(`bug: an import of ${request.specifier} in non-ember package at ${request.fromFile}`);
-    }
-
     return logTransition('test-support', request, request.virtualize(resolve(pkg.root, '-embroider-test-support.js')));
   }