Add tenancy access info to serialized user in threadcontext

[cwperks]

Description

This PR adds information about the user's level of access to the requested tenant when serializing the user into the threadcontext. There can be 1 of 3 levels of access. 1) No Access - user has no access to the requested tenant, 2) Read Only - User has read only access to the requested tenant and 3) Write access - user can save saved objects to the requested tenant

Check List

• New functionality includes testing
• New functionality has been documented
• New Roles/Permissions have a corresponding security dashboards plugin PR
• API changes companion pull request created
• Commits are signed per the DCO using --signoff

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.

[cwperks]

FYI see the comment thread on my fork over here too: cwperks#63 (comment)

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.75%. Comparing base (5dc83be) to head (006d839).
⚠️ Report is 8 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5519      +/-   ##
==========================================
- Coverage   72.78%   72.75%   -0.03%     
==========================================
  Files         398      398              
  Lines       24641    24667      +26     
  Branches     3747     3755       +8     
==========================================
+ Hits        17934    17947      +13     
- Misses       4878     4883       +5     
- Partials     1829     1837       +8     

Files with missing lines	Coverage Δ
...earch/security/privileges/PrivilegesEvaluator.java	75.48% <100.00%> (+0.63%)	⬆️

... and 12 files with indirect coverage changes

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[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/security/backport-2.19 2.19
# Navigate to the new working tree
pushd ../.worktrees/security/backport-2.19
# Create a new branch
git switch --create backport/backport-5519-to-2.19
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 7ac993bcc3e1af506543594133700145e5be5101
# Push it to GitHub
git push --set-upstream origin backport/backport-5519-to-2.19
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/security/backport-2.19

Then, create a pull request where the base branch is 2.19 and the compare/head branch is backport/backport-5519-to-2.19.

[cwperks]

I will open up a manual backport and corresponding PR to common utils repo