Fix model/connector update API to address security concern

[b4sjoo]

Description

Fix the 500 internal service error reported in the pen test. All parsing errors should return 400 error code showing it's coming from users. Meanwhile fix the model version unable to auto-bump bug when register the model to new model group.

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• 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.

[codecov]

Codecov Report

Merging #1595 (c8898e3) into 2.x (a87283f) will decrease coverage by 0.03%.
The diff coverage is 98.43%.

@@             Coverage Diff              @@
##                2.x    #1595      +/-   ##
============================================
- Coverage     80.66%   80.63%   -0.03%     
+ Complexity     4177     4171       -6     
============================================
  Files           399      399              
  Lines         16815    16806       -9     
  Branches       1815     1815              
============================================
- Hits          13564    13552      -12     
- Misses         2535     2538       +3     
  Partials        716      716              

Flag	Coverage Δ
ml-commons	80.63% <98.43%> (-0.03%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
...in/java/org/opensearch/ml/common/MLModelGroup.java	85.32% <ø> (ø)
.../action/connector/GetConnectorTransportAction.java	78.04% <100.00%> (+0.54%)	⬆️
...tion/connector/UpdateConnectorTransportAction.java	94.36% <100.00%> (ø)
...search/ml/helper/ConnectorAccessControlHelper.java	74.15% <100.00%> (ø)
...a/org/opensearch/ml/model/MLModelGroupManager.java	83.20% <100.00%> (+1.19%)	⬆️
...rg/opensearch/ml/plugin/MachineLearningPlugin.java	96.24% <ø> (ø)
...pensearch/ml/rest/RestMLUpdateConnectorAction.java	100.00% <ø> (+9.52%)	⬆️
...rg/opensearch/ml/rest/RestMLUpdateModelAction.java	100.00% <100.00%> (ø)
.../org/opensearch/ml/settings/MLCommonsSettings.java	100.00% <ø> (ø)
...pensearch/ml/settings/MLFeatureEnabledSetting.java	85.71% <ø> (+2.38%)	⬆️
... and 2 more

... and 7 files with indirect coverage changes

[opensearch-trigger-bot]

The backport to feature/agent_framework_dev failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-feature/agent_framework_dev feature/agent_framework_dev
# Navigate to the new working tree
cd .worktrees/backport-feature/agent_framework_dev
# Create a new branch
git switch --create backport/backport-1595-to-feature/agent_framework_dev
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 e388f1a3939b7d262981d8ccb84e7d528183f39e
# Push it to GitHub
git push --set-upstream origin backport/backport-1595-to-feature/agent_framework_dev
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-feature/agent_framework_dev

Then, create a pull request where the base branch is feature/agent_framework_dev and the compare/head branch is backport/backport-1595-to-feature/agent_framework_dev.