fix(gatsby): fix broken GraphQL resolver tracing (#29015)

* fix(gatsby): fix broken GraphQL resolvers tracing

* end activity for sync resolvers

Author: vladar

packages/gatsby/src/schema/resolvers.ts

@@ -566,13 +566,23 @@ export function wrappingResolver<TSource, TArgs>(
       )
       activity.start()
     }
-    try {
-      return resolver(parent, args, context, info)
-    } finally {
+    const result = resolver(parent, args, context, info)
+
+    if (!activity) {
+      return result
+    }
+
+    const endActivity = (): void => {
       if (activity) {
         activity.end()
       }
     }
+    if (typeof result?.then === `function`) {
+      result.then(endActivity, endActivity)
+    } else {
+      endActivity()
+    }
+    return result
   }
 }