Fix handling of Types::CiConfiguration::Sast::InputType parameter

What does this MR do and why?

For the Mutations::Security::CiConfiguration::ConfigureSast, it accepts an argument ::Types::CiConfiguration::Sast::InputType.

The data structure behind this InputType come from the GraphQL gem. This type of data should never be passed into once of our services raw, as the services code know nothing about GraphQL or it's data structures.

When the GraphQL gem was upgraded in !27536 (merged), the underlying data structure changed, and the service code is no longer able to extract the necessary data.

Transform the argument into a hash and pass to the service, and update the ::Security::CiConfiguration::SastCreateService to properly handle it.

This was discovered by a failing QA test, #364141 (closed)

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Related to #364141 (closed)