[CT-945] Support updating raw_sql to raw_code and compiled_sql to compiled_code

[ChenyuLInx]

We updated the attribute name in dbt-core given SQL is no longer the only language dbt support.
But given the fact that we want to depreciate dbt-rpc by the end of the year, we think it is best to convert the attribute name back to what it used to be to make this transition smoother for existing rpc server user.

In order to do it, dbt-rpc would:

• be able to pull results from both new name(raw_code, compiled_cdoe) and the old name(raw_sql, compiled_sql) from dbt-core
• return results in API call will still use the old name(raw_sql, compiled_sql).
• for manifest.json, we just return the current manifest, there's no modification of it. Meaning that new names are going to be used there