[BUG] FIX vector usuage example

[sadath-12]

Description

The yaml file shown under https://www.siglens.com/siglens-docs/log-ingestion/vector is not 100% correct . It says err variable is not used

Fix: consider using ! operator which might fix this

Steps to Reproduce

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1. ...

Expected Behavior

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Environment

• Commit Hash: [e.g. 9ed5f0a]
• OS: [e.g. MacOS 14.1.1 on apple silicon]
• Browser and Version (if applicable): [e.g. chrome 119.0.6045.159 arm64, safari 19616.2.9.11.7]

(Optional) Additional Context

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