Increase ulimit in Dockerfile to 81920

[appsol]

Summary

https://app.shortcut.com/connectedplaces/story/4199/increase-ulimit

• Increased ulimit for open files from 40960 to 81920

Development checklist

• Changes have been made to the API?
  • If so, the OpenAPI specification has been updated
• Database migrations have been added?
  • If so, the MySQL Workbench ERD has been updated
• The code has been linted ./develop composer fix:style

Release checklist

If there are any actions that must be performed as part of the release, then
create a checklist for them here.

Notes

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