feat(nginx): lower client_max_body_size

[RisingOpsNinja]

Description of the change

This change lowers the Nginx configuration client_max_body_size to match the default PHP_UPLOAD_LIMIT of 512 MiB in the php-fpm docker image and also match the default nginx configuration in the Nextcloud admin manual after enabling fastcgi_request_buffering #855

Benefits

Lowering the configuration will reduces memory, disk pressure and also lowers risk of resource exhaustion.

client_max_body_size is set to 10 GiB which is an exceptionally large default value.

Possible drawbacks

Some clients may not support chunked uploads and send the whole file in a single request. Nginx will reject the request if it is larger then client_max_boy_size.

Checklist

• I have read the CONTRIBUTING.md doc.
• DCO has been signed off on the commit.
• Chart version bumped in Chart.yaml according to semver.
• (optional) Parameters are documented in the README.md