Rename callmodel to callLlm in quickstart.mdx (#1158)

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Author: mohitsingla46

src/oss/langgraph/quickstart.mdx

@@ -814,7 +814,7 @@ def call_llm(messages: list[BaseMessage]):
 ```typescript
 import { task, entrypoint } from "@langchain/langgraph";
 import { SystemMessage } from "@langchain/core/messages";
-const callmodel = task({ name: "callLlm" }, async (messages: BaseMessage[]) => {
+const callLlm = task({ name: "callLlm" }, async (messages: BaseMessage[]) => {
   return modelWithTools.invoke([
     new SystemMessage(
       "You are a helpful assistant tasked with performing arithmetic on a set of inputs."
@@ -1097,7 +1097,7 @@ const modelWithTools = model.bindTools(tools);
 
 import { task, entrypoint } from "@langchain/langgraph";
 import { SystemMessage } from "@langchain/core/messages";
-const callmodel = task({ name: "callLlm" }, async (messages: BaseMessage[]) => {
+const callLlm = task({ name: "callLlm" }, async (messages: BaseMessage[]) => {
   return modelWithTools.invoke([
     new SystemMessage(
       "You are a helpful assistant tasked with performing arithmetic on a set of inputs."