[language][bytecode verifier] remove unreachable code/file unit_tests.rs
[language][bytecode verifier] remove unreachable code/file unit_tests.rs

Closes: #1087
Approved by: huitseeker

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