Adding new maintainers

[vikasvb90]

Description

Adding @tandonks @shiv0408 @soosinha to maintainers list.

Issues Resolved

[List any issues this PR will resolve]

Check List

• Commits are signed per the DCO using --signoff

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[vikasvb90]

@bowenlan-amzn @Hailong-am @RamakrishnaChilaka
Please provide your approval on this PR. (Also, please leave it open after approval)

[peterzhuamazon]

Pending GitHub Request: opensearch-project/.github#248

[opensearch-trigger-bot]

The backport to 2.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/index-management-dashboards-plugin/backport-2.x 2.x
# Navigate to the new working tree
pushd ../.worktrees/index-management-dashboards-plugin/backport-2.x
# Create a new branch
git switch --create backport/backport-1235-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 a32b66975bf90be8090eb614a38d19880730e0b7
# Push it to GitHub
git push --set-upstream origin backport/backport-1235-to-2.x
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/index-management-dashboards-plugin/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-1235-to-2.x.