Evaluate if refactor of CreateMutation.Build() to accept RuntimeConfig object is beneficial

PR https://github.com/Azure/data-api-builder/pull/2116 introduces a new parameter called `isMultipleCreateOperationEnabled` to `CreateMutationBuilder.Build()` method.

`isMultipleCreateOperationEnabled` can be computed using `RuntimeConfig.IsMultipleCreateOperationEnabled()`.
`CreateMutationBuilder.Build()` method accepts another parameter called `entities` of type `RuntimeEntities`. `entities` originates from `RuntimeConfig.RuntimeEntities`

Evaluate if it is beneficial to refactor `CreateMutationBuilder.Build()` method to accept `RuntimeConfig` object instead of two parameters separately.

Original discussion: https://github.com/Azure/data-api-builder/pull/2116#discussion_r1536631102