sc_executor_wasmtime: Enable turning off of parallel compilation

[pepyakin]

For implementing the pre-checking game we need to perform compilation process in a single-thread.

This should be passed as a bool parallel_compilation in sc_executor_wasmtime::Semantics, which will be passed into the same name configuration in wasmtime::Config.

The bool seems to be more fitting into Config rather than Semantics. But that only the naming issue I believe. Semantics dictate the compile time configuration and Config sets runtime behavior. The Semantics can be renamed as part of the PR.

This is blocked by #9605