[api] add /spec.html and /openapi.yaml routes doc
[api] add /spec.html and /openapi.yaml routes doc

Closes: #9557

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