how to set default value for Automatically open requisition for sourcing

Summary:

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Hi,

I understand under configuration we have an option to select values from drop down for Automatically open requisition for sourcing. We want to make ' posted both internally and externally' as default , how can we do that ?

Version (include the version you are using, if applicable):

24b

Code Snippet (add any code snippets that support your topic, if applicable):