[AUTO] Increment version to 2.15.0-SNAPSHOT

[opensearch-trigger-bot]

• Incremented version to 2.15.0-SNAPSHOT.

[jmazanec15]

BWC tests are failing with missing knn and ml-commons dependencies. Both k-NN and ml-commons are failing:

 * What went wrong:
A problem occurred evaluating root project 'neural-search'.
> Could not resolve all files for configuration ':zipArchive'.
   > Could not find org.opensearch.plugin:opensearch-knn:2.15.0.0-SNAPSHOT.
     Searched in the following locations:

[martin-gaievski]

Dependency repos knn and ml-commons got upgraded 2.x to 2.15, adding bwc related changes and resuming efforts for upgrade

[opensearch-trigger-bot]

The backport to main failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-main main
# Navigate to the new working tree
cd .worktrees/backport-main
# Create a new branch
git switch --create backport/backport-730-to-main
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 398a46534cae7c4c06423d6dad6207163c916b46
# Push it to GitHub
git push --set-upstream origin backport/backport-730-to-main
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-main

Then, create a pull request where the base branch is main and the compare/head branch is backport/backport-730-to-main.