Fix suggestion options and mapping char filter

[swallez]

Fixes issues found in the Java client:

• MappingCharFilter.mapping is optional. See Regression Bug: Char Filter requires mappings field even when mappings_path is used elasticsearch-java#318
• Suggester options are arrays (with their usual leniency rules). See TermSuggest options should be an array elasticsearch-java#214

[sethmlarson]

LGTM

[github-actions]

Following you can find the validation results for the API you have changed.

API	Status	Request	Response
search	🔴	1469/1524	1493/1506

You can validate this API yourself by using the make validate target.

[github-actions]

The backport to 7.17 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-7.17 7.17
# Navigate to the new working tree
cd .worktrees/backport-7.17
# Create a new branch
git switch --create backport-1783-to-7.17
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick --mainline 1 3c092a8a0a88fd011a976c836049fcedec1fe3c3
# Push it to GitHub
git push --set-upstream origin backport-1783-to-7.17
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-7.17

Then, create a pull request where the base branch is 7.17 and the compare/head branch is backport-1783-to-7.17.