Refactor test workflow to separate bwc tests

[Swiddis]

Description

Makes linux test failures more visible by splitting out the failing BWC tests to their own action. I'm not sure how to fix the BWC tests, I've been told they start failing semi-regularly due to external factors so it seems like it's a wise decision to keep it separate from more reliable tests.

Related Issues

N/A

Check List

• New functionality includes testing.
• New functionality has been documented.
• New functionality has javadoc added.
• New functionality has a user manual doc added.
• 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.

[MaxKsyunz]

lgtm

[Swiddis]

Have spent several hours trying to debug the actual BWC test failures but it's a bit outside my skillset right now -- anyone have pointers?

[noCharger]

let's create an issue to track BWC seperately. thx!

[Swiddis]

#3089

[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/sql/backport-2.x 2.x
# Navigate to the new working tree
pushd ../.worktrees/sql/backport-2.x
# Create a new branch
git switch --create backport/backport-3070-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 f4def3111020bf5147bffce666e9efbb5738820e
# Push it to GitHub
git push --set-upstream origin backport/backport-3070-to-2.x
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/sql/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-3070-to-2.x.

[Swiddis]

Skipping backport on this since the tests are failing so heavily there that the benefit would be near-zero. main is comparatively much more "on the front lines" for upcoming BWC issues