Filter license by hosting

I can’t find any examples on the Marketplace REST API documentation of what the query parameter should look like. I am referring to https://developer.atlassian.com/platform/marketplace/rest/v2/api-group-reporting/#api-vendors-vendorid-reporting-licenses-get. What does “Style: form” refer to? Is there a resource that describes the “form” style?

i need to filter license by hosting or any parameter of type array<string>