Disable some limits when JSON parsing OpenAPI data

What does this MR do and why?

This MR disables two limits when JSON parsing OpenAPI data in our rake tasks.

• max_total_elements
• max_json_size_bytes

Currently we're tripping the max_total_elements limit when we generate or check our Open API YAML data.

This MR also disables the max_json_size_bytes limit as that seems likely to be tripped in future too.

How to set up and validate locally

On master, run either of these commands:

bundle exec rake gitlab:openapi:v2:generate
bundle exec rake gitlab:openapi:v2:check_docs

You'll see the error:

Generating OpenAPI v2 docs with GITLAB_SIMULATE_SAAS=false (override with OPENAPI_SIMULATE_SAAS=true)
rake aborted!
JSON::ParserError: Too many total parameters (JSON::ParserError)
/Users/luke/Sites/gdk/gitlab/lib/gitlab/json/safe_parser.rb:169:in `raise_human_readable_error!'
/Users/luke/Sites/gdk/gitlab/lib/gitlab/json/safe_parser.rb:136:in `rescue in parse'
/Users/luke/Sites/gdk/gitlab/lib/gitlab/json/safe_parser.rb:130:in `parse'
/Users/luke/Sites/gdk/gitlab/lib/gitlab/json/safe_parser.rb:96:in `parse'
/Users/luke/Sites/gdk/gitlab/lib/tasks/gitlab/openapi/v2.rake:45:in `block (4 levels) in <main>'

Caused by:
Oj::Parser::TotalElementsError: Too many elements! (Oj::Parser::TotalElementsError)
/Users/luke/Sites/gdk/gitlab/lib/gitlab/json/safe_parser.rb:134:in `parse'
/Users/luke/Sites/gdk/gitlab/lib/gitlab/json/safe_parser.rb:134:in `parse'
/Users/luke/Sites/gdk/gitlab/lib/gitlab/json/safe_parser.rb:96:in `parse'
/Users/luke/Sites/gdk/gitlab/lib/tasks/gitlab/openapi/v2.rake:45:in `block (4 levels) in <main>'

Run the commands on this branch and the YAML files should compile / be checked successfully.

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.