Fix: Kafka metadata fixes

[prdpx7]

This PR fixes the following issues:

1. Set Kafka's record timestamp as current timestamp
2. Set ReqID as Kafka's record key instead of empty string

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[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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