grafana/toolkit: Resolve modules correctly (#21216)

packages/grafana-toolkit/src/config/webpack.plugin.config.ts

@@ -29,7 +29,8 @@ export const findModuleFiles = async (base: string, files?: string[], result?: s
   result = result || [];
 
   if (files) {
-    files.forEach(async file => {
+    await Promise.all(
+      files.map(async file => {
         const newbase = path.join(base, file);
         if (fs.statSync(newbase).isDirectory()) {
           result = await findModuleFiles(newbase, await readdirPromise(newbase), result);
@@ -40,7 +41,8 @@ export const findModuleFiles = async (base: string, files?: string[], result?: s
             result.push(newbase);
           }
         }
-    });
+      })
+    );
   }
   return result;
 };