Increase PumaWorkerKiller memory limit for dev

What does this MR do?

Add additional 200mb to PumaWorkerKiller limits (both for the master and workers) in development ENV.

Resolves gitlab-development-kit#672 (closed)

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content