[Admin] Add @ruanyl as a maintainer

[SuZhou-Joe]

Description

Updates MAINTAINERS.md and .github/CODEOWNERS.

Here are their current merge contributions, total contributions, and issues:

• https://github.com/opensearch-project/OpenSearch-Dashboards/pulls?q=is%3Apr+is%3Amerged+author%3Aruanyl+
• https://github.com/opensearch-project/OpenSearch-Dashboards/pulls?q=is%3Apr+author%3Aruanyl+
• https://github.com/opensearch-project/OpenSearch-Dashboards/issues?q=is%3Aissue+ruanyl+is%3Aopen

Issue:
n/a

Signed-off-by: Su Zhou suzhou@amazon.com

[kavilla]

@opensearch-project/admin could you add @ruanyl to a maintainer.

[opensearch-trigger-bot]

The backport to 1.x 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-Dashboards/backport-1.x 1.x
# Navigate to the new working tree
pushd ../.worktrees/OpenSearch-Dashboards/backport-1.x
# Create a new branch
git switch --create backport/backport-5982-to-1.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 eeb68ca162f64f4d3b11a82f290029851b5c4e82
# Push it to GitHub
git push --set-upstream origin backport/backport-5982-to-1.x
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/OpenSearch-Dashboards/backport-1.x

Then, create a pull request where the base branch is 1.x and the compare/head branch is backport/backport-5982-to-1.x.