Revert "[Backport 2.19-dev] [AUTO] Increment version to 2.19.5-SNAPSHOT"

[LantaoJin]

Reverts #5077 which cause CI failing, e.g. https://github.com/opensearch-project/sql/actions/runs/21615168490/job/62292227578?pr=5104

The root cause is that the artifacts of geospatial 2.15.0-SNAPSHOT is still not uploaded, ref opensearch-project/geospatial#824 (comment)

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[LantaoJin]

Close as the artifacts of geospatial 2.15.0-SNAPSHOT uploaded now.