Actually use ConnectionConfiguration.DefaultMemoryStreamFactory

[djimenez]

Description

Use DefaultMemoryStreamFactory static property for the default in ConnectionConfiguration - currently the private member is initialized to a different value, which is confusing.

Issues Resolved

Resolves #551

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[Xtansia]

Thanks @djimenez!

Only other thing that you'll need to do is add an item into the CHANGELOG.md under a ### Changed heading inside the ## [Unreleased] section.

[opensearch-trigger-bot]

The backport to 1.x 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-1.x 1.x
# Navigate to the new working tree
cd .worktrees/backport-1.x
# Create a new branch
git switch --create backport/backport-552-to-1.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 80854014b7376f6882ebb3010c0309a0f9774808
# Push it to GitHub
git push --set-upstream origin backport/backport-552-to-1.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-1.x

Then, create a pull request where the base branch is 1.x and the compare/head branch is backport/backport-552-to-1.x.