Add @yupeng9 as a maintainer

[andrross]

Following the nomination process, I have nominated and other maintainers have agreed to add Yupeng Fu (@yupeng9) as a co-maintainer of the OpenSearch repository. Yupeng has kindly accepted the invitation.

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Yupeng has been an active contributor to OpenSearch, most notably spearheading the introduction of pull-based ingestion into the 3.0 release. Overall, he has authored 9 issues, merged 10 PRs, and provided feedback on 23 PRs.

For the pull-based ingestion feature, Yupeng created the initial RFC to solicit feedback, produced a design, and then authored the PR that introduced the entirely new pull-based ingestion engine into the core with a pluggable interface for different ingestion source implementations. From there he created a meta issue detailing the next steps and guided other developers as the feature was completed for the upcoming 3.0 release. He also stayed closely engaged and followed up with a quick fix for a newly introduced flaky test. Yupeng has also engaged with areas of the project unrelated to pull-based ingestion by reviewing other issues and PRs (examples: 1 2 3 4). Most recently Yupeng has opened an RFC for making OpenSearch more cloud native, though that effort is still early days!

Related issue in the .github repo: opensearch-project/.github#329

Check List

• Functionality includes testing.
• API changes companion pull request created, if applicable.
• Public documentation issue/PR created, if applicable.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[andrross]

This PR is in draft pending the permissions update in opensearch-project/.github#329

[opensearch-trigger-bot]

The backport to 2.19 failed:

The process '/usr/bin/git' failed with exit code 128

To backport manually, run these commands in your terminal:

# Navigate to the root of your repository
cd $(git rev-parse --show-toplevel)
# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add ../.worktrees/OpenSearch/backport-2.19 2.19
# Navigate to the new working tree
pushd ../.worktrees/OpenSearch/backport-2.19
# Create a new branch
git switch --create backport/backport-18234-to-2.19
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 803884f0ee917ea5be856601bcccd2a756b39bae
# Push it to GitHub
git push --set-upstream origin backport/backport-18234-to-2.19
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/OpenSearch/backport-2.19

Then, create a pull request where the base branch is 2.19 and the compare/head branch is backport/backport-18234-to-2.19.