chore: improve error msg

[camilesing]

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Summary

for issue: #18835

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Explain why

Type of change

• Bug Fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• Documentation Update
• Refactoring
• Performance Improvement
• Other (please describe): error msg improve

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This change is 

[github-actions]

🤖 CI Job Analysis

Workflow: 18802040232

📊 Summary

• Total Jobs: 83
• Failed Jobs: 2
• Retryable: 0
• Code Issues: 2

❌ NO RETRY NEEDED

All failures appear to be code/test issues requiring manual fixes.

🔍 Job Details

• ❌ linux / test_unit: Not retryable (Code/Test)
• ❌ linux / test_stateful_cluster: Not retryable (Code/Test)

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🤖 About

Automated analysis using job annotations to distinguish infrastructure issues (auto-retried) from code/test issues (manual fixes needed).

[BohuTANG]

Hi,

CI fails:

    thread 'read::row_based::formats::ndjson::block_builder::test::test_json_decode_error' panicked at src/query/storages/stage/src/read/row_based/formats/ndjson/block_builder.rs:238:9:
    assertion `left == right` failed
      left: "EOF while parsing an object at line 1, position 0 of size 1 for File 'mock_file'"
     right: "EOF while parsing an object at pos 0 of size 1"
    note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

[camilesing]

@BohuTANG I'll fix it