Related to microsoftgraph/msgraph-sdk-java#2163 and microsoftgraph/msgraph-sdk-dotnet#2671 (comment)

In a scenario where all the properties in the request body are optional such as an odata action with all parameters being optional, we should set the requestBody.required = false in the generated openApi description otherwise explictly set it to true.

https://spec.openapis.org/oas/v3.0.3.html#fixed-fields-10

This will unlock the generation of request body parameters in the SDKs as optional parameters in the builders to prevent breaking changes in scenarios where optional parametes are added.