fix(docs): typo in the "Pass private state between nodes" output example. (#1183)

## Overview
In the example output in the "Pass private state between nodes" section,
the print statement shown above was not written correctly.

## Type of change

**Type:** Fix typo

## Related issues/PRs

- GitHub issue: None
- Feature PR: None

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- Linear issue:
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## Checklist
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- [x] I have read the [contributing guidelines](README.md)
- [ ] I have tested my changes locally using `docs dev`
- [ ] All code examples have been tested and work correctly
- [ ] I have used **root relative** paths for internal links
- [ ] I have updated navigation in `src/docs.json` if needed
- I have gotten approval from the relevant reviewers
- (Internal team members only / optional) I have created a preview
deployment using the [Create Preview Branch
workflow](https://github.com/langchain-ai/docs/actions/workflows/create-preview-branch.yml)

## Additional notes
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Author: 35bytes

src/oss/langgraph/use-graph-api.mdx

@@ -595,14 +595,14 @@ print(f"Output of graph invocation: {response}")
 
 ```
 Entered node `node_1`:
-    ut: {'a': 'set at start'}.
-    urned: {'private_data': 'set by node_1'}
+    Input: {'a': 'set at start'}.
+    Returned: {'private_data': 'set by node_1'}
 Entered node `node_2`:
-    ut: {'private_data': 'set by node_1'}.
-    urned: {'a': 'set by node_2'}
+    Input: {'private_data': 'set by node_1'}.
+    Returned: {'a': 'set by node_2'}
 Entered node `node_3`:
-    ut: {'a': 'set by node_2'}.
-    urned: {'a': 'set by node_3'}
+    Input: {'a': 'set by node_2'}.
+    Returned: {'a': 'set by node_3'}
 
 Output of graph invocation: {'a': 'set by node_3'}
 ```