Use ResultProcessor in ElasticsearchPartQuery to build PartTree [DATAES-969]

[spring-projects-issues]

sothawo opened DATAES-969 and commented

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Affects: 3.2.11 (Moore SR11), 4.0.5 (Neumann SR5), 4.1 GA (2020.0.0), 4.2 M1 (2021.0.0)

Referenced from: pull request #546

Backported to: 4.1.1 (2020.0.1), 4.0.6 (Neumann SR6), 3.2.12 (Moore SR12)