Adding decompress_archive_file_timeout to application settings

What does this MR do and why?

Currently the hardcoded timeout of 210seconds for decompressing archived files is too short for some customers. If we were to move this to application settings, self-managed users can set their own timeouts depending on how long they want to wait.

Screenshots or screen recordings

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Before	After

How to set up and validate locally

1. Ensure import/export still works.
2. Timeout is changeable, by changing the timeout limit in the UI and then going into rails console to check Gitlab::CurrentSettings.current_application_settings.decompress_archive_file_timeout or the new database column decompress_archive_file_timeout should reflect the new changed timeout value

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #421432 (closed)