Update validator for index.routing.allocation.total_primary_shards_per_node for index update requests.

[pandeydivyansh1803]

Description

When attempting to update the index.routing.allocation.total_primary_shards_per_node setting for an existing index in a remote store enabled cluster, an error is encountered stating that this setting can only be used with remote store enabled clusters, despite the cluster actually being remote store enabled.
Changes in this PR, updates the validator for update index setting. The change aims to resolve bug identified in #17295

Related Issues

Resolves #17473

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.
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[github-actions]

❌ Gradle check result for 7ffccca: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

✅ Gradle check result for 7ffccca: SUCCESS

[codecov]

Codecov Report

Attention: Patch coverage is 21.42857% with 11 lines in your changes missing coverage. Please review.

Project coverage is 72.45%. Comparing base (82bbdfb) to head (7ffccca).
Report is 6 commits behind head on main.

Files with missing lines	Patch %	Lines
...luster/metadata/MetadataUpdateSettingsService.java	21.42%	10 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main   #17529      +/-   ##
============================================
- Coverage     72.59%   72.45%   -0.14%     
+ Complexity    65798    65748      -50     
============================================
  Files          5311     5311              
  Lines        304888   304901      +13     
  Branches      44212    44214       +2     
============================================
- Hits         221323   220926     -397     
- Misses        65501    65871     +370     
- Partials      18064    18104      +40     

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[linuxpi]

Codecov Report

Attention: Patch coverage is 21.42857% with 11 lines in your changes missing coverage. Please review.

Project coverage is 72.45%. Comparing base (82bbdfb) to head (7ffccca).
Report is 4 commits behind head on main.

Files with missing lines Patch % Lines
...luster/metadata/MetadataUpdateSettingsService.java 21.42% 10 Missing and 1 partial ⚠️
Additional details and impacted files

☔ View full report in Codecov by Sentry. 📢 Have feedback on the report? Share it here.
🚀 New features to boost your workflow:

Covered in ITs

[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/OpenSearch/backport-2.x 2.x
# Navigate to the new working tree
pushd ../.worktrees/OpenSearch/backport-2.x
# Create a new branch
git switch --create backport/backport-17529-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 73882054afcdb74244c07c5be1f54a629ffd0bc2
# Push it to GitHub
git push --set-upstream origin backport/backport-17529-to-2.x
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/OpenSearch/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-17529-to-2.x.