Update elasticsearch requirement in /batch_processing

Updates the requirements on [elasticsearch](https://github.com/elastic/elasticsearch-py) to permit the latest version.
- [Release notes](https://github.com/elastic/elasticsearch-py/releases)
- [Commits](elastic/elasticsearch-py@7.0.0...v8.12.1)

---
updated-dependencies:
- dependency-name: elasticsearch
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

batch_processing/requirements.txt

@@ -1,4 +1,4 @@
 multiprocessing~=2.6
 time~=1.0
-elasticsearch~=7.0
+elasticsearch~=8.12
 argparse~=1.4