fix(java): download java-db once

[DmitriyLewen]

Description

After #5273 we download java-db for each layer with jar files (for image mode), but this should be done once per run.
Also we need to create new Client for each PostAnalyze function instead of overwriting client from javaLibraryAnalyzer.

Related issues

• Close bug(java): Trivy downloads trivy-java-db multiple times in one run #5441

Related PRs

• fix(java): close java-db client #5273

Checklist

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