feat: make init job ttlSecondsAfterFinished configurable and default 1h

[simonhir]

What this PR does / why we need it

• Allow configuration of init Job ttlSecondsAfterFinished
• Set default of init Job ttlSecondsAfterFinished to 1h as 5m seams not really like a production useful value
  • (In my opinion 1h is a good compromise between as short as possible but useful)

Which issue this PR fixes

• closes Allow setting ttlSecondsAfterFinished on the init job #359

Checklist

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• Chart Version bumped
• [ ] Upgrading instructions are documented in the zammad/README.md (not required)