Fix test flake introduced by changes to MockLink (#12565)

Author: jerelmiller

.size-limits.json

@@ -1,6 +1,6 @@
 {
-  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (CJS)": 42984,
-  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (production) (CJS)": 38432,
-  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\"": 32968,
-  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (production)": 27861
+  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (CJS)": 42972,
+  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (production) (CJS)": 38452,
+  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\"": 32914,
+  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (production)": 27847
 }

src/__tests__/mutationResults.ts

@@ -650,10 +650,12 @@ describe("mutation results", () => {
       {
         request: { query: queryTodos },
         result: queryTodosResult,
+        delay: 0,
       },
       {
         request: { query: mutationTodo },
         result: mutationTodoResult,
+        delay: 0,
       }
     );