Add tenancy access info to serialized user in threadcontext

[cwperks]

Description

Companion security PR: opensearch-project/security#5519

This PR adds additional information about the requested tenant and the level of access the authenticated user has to that tenant. i.e. one of No Access, Write access or Read access.

Related Issues

Resolves opensearch-project/reporting#1099

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.

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.

[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/common-utils/backport-2.19 2.19
# Navigate to the new working tree
pushd ../.worktrees/common-utils/backport-2.19
# Create a new branch
git switch --create backport/backport-857-to-2.19
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 9bb579f23dd6c7cc7a8a9a55c18ad0a1c4e2e770
# Push it to GitHub
git push --set-upstream origin backport/backport-857-to-2.19
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/common-utils/backport-2.19

Then, create a pull request where the base branch is 2.19 and the compare/head branch is backport/backport-857-to-2.19.

[dhrubo-os]

When are we supposed to get this field? In ml-commons, unit tests are failing due to this (assertion error).