fix(stream): continue on iterator error values

if the iterator errors when attempting to get the next value, we can assume subsequent calls to next will also error, and abort, but if we successfully get the next value, but it ends up triggering an error, we can continue, optimistic that the next value will not do so.

src/execution/__tests__/lists-test.js

@@ -139,6 +139,25 @@ describe('Execute: Accepts async iterables as list value', () => {
     });
   });
 
+  it('Handles an AsyncGenerator function where an intermediate value triggers an error', async () => {
+    async function* listField() {
+      yield await 'two';
+      yield await {};
+      yield await 4;
+    }
+
+    expect(await complete({ listField })).to.deep.equal({
+      data: { listField: ['two', null, '4'] },
+      errors: [
+        {
+          message: 'String cannot represent value: {}',
+          locations: [{ line: 1, column: 3 }],
+          path: ['listField', 1],
+        },
+      ],
+    });
+  });
+
   it('Handles errors from `completeValue` in AsyncIterables', async () => {
     async function* listField() {
       yield await 'two';

src/execution/execute.js

@@ -901,8 +901,6 @@ function completeAsyncIteratorValue(
               pathToArray(fieldPath),
             );
             handleFieldError(error, itemType, exeContext);
-            resolve(completedResults);
-            return;
           }
 
           next(index + 1, completedResults);