[libra_fuzzer] don't depend on vm_runtime any more
[libra_fuzzer] don't depend on vm_runtime any more

Now that the vm_runtime_types crate has been split out of vm_runtime, we
no longer have a dependency on vm_runtime.

libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,libra/libra,libra/libra,aptos-labs/aptos-core