chore: Import config-utils

[Techassi]

This PR imports config-utils, similar to what we already did for containerdebug back in #1233.

Originally implemented in and imported from https://github.com/stackabletech/config-utils.

Import commands

cd /tmp

git clone git@github.com:stackabletech/config-utils.git
git clone git@github.com:stackabletech/operator-rs.git

touch message.py
touch committer.py

cd config-utils
git filter-repo \
  --path src/ \
  --path tests/ \
  --path .gitattributes \
  --path .gitignore \
  --path Cargo.toml \
  --path README.md \
  --path CHANGELOG.md \
  --path LICENSE \
  --message-callback ../message.py \
  --commit-callback ../committer.py \
  --to-subdirectory-filter \
  crates/config-util

cd ../operator-rs
git remote add config-utils ../config-utils
git fetch config-utils --no-tags
git merge --allow-unrelated-histories --message "chore: Import config-utils" config-utils/main
git rebase --exec 'git commit --amend --no-edit --no-verify' origin/main
git checkout -b chore/import-config-utils
# Do cleanup/integration
git push

See more details here: https://github.com/stackabletech/snippets/blob/main/snippets/import-repo-into-repo.md

[dervoeti]

Just one optional nit