Fixed incorrect document order for nested aggregations in hybrid query

[martin-gaievski]

Description

Fixed logic for getting scorers for sub-queries of hybrid query. Today we're getting document ids and scorers from a pre-sorted collection of doc iterators, but that does not work for deeply nested aggregations because that order can change dynamically.

I have added an integ test for this scenario, it will for 2.15.

Related Issues

#955

Check List

• New functionality includes testing.
• New functionality has been documented.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff.
• Public documentation issue/PR created.

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[martin-gaievski]

put in release notes file directly because notes were pulled from CHANGELOG for 2.18 release

[vibrantvarun]

LGTM. Thanks

[opensearch-trigger-bot]

The backport to 2.x 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-2.x 2.x
# Navigate to the new working tree
cd .worktrees/backport-2.x
# Create a new branch
git switch --create backport/backport-956-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 0df59c6ec8733b86f6c8537b1fabe37c21721242
# Push it to GitHub
git push --set-upstream origin backport/backport-956-to-2.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-956-to-2.x.

[opensearch-trigger-bot]

The backport to 2.18 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-2.18 2.18
# Navigate to the new working tree
cd .worktrees/backport-2.18
# Create a new branch
git switch --create backport/backport-956-to-2.18
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 0df59c6ec8733b86f6c8537b1fabe37c21721242
# Push it to GitHub
git push --set-upstream origin backport/backport-956-to-2.18
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-2.18

Then, create a pull request where the base branch is 2.18 and the compare/head branch is backport/backport-956-to-2.18.