Make apache-arrow an optional dependency

[JoshMock]

No description provided.

[prodsecmachine]

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[github-actions]

🔍 Preview links for changed docs

• docs/release-notes/index.md

[github-actions]

✅ Vale Linting Results

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[elastic-vault-github-plugin-prod]

The backport to 9.4 failed:

The process '/usr/bin/git' failed with exit code 128

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-9.4 9.4
# Navigate to the new working tree
cd .worktrees/backport-9.4
# Create a new branch
git switch --create backport-3246-to-9.4
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 7b3bbde9e40fa97032305c1838ca808566aa3e92
# Push it to GitHub
git push --set-upstream origin backport-3246-to-9.4
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-9.4

Then, create a pull request where the base branch is 9.4 and the compare/head branch is backport-3246-to-9.4.

[github-actions]

AI Backport Resolver created a backport PR (no conflicts): #3247