Support aliases in compiled_query:avro_schema()

[Alexander Turenko]

We should generate a schema that matches any possible result. Now using aliases brokes this property.

It is follow up of #262.

[Alexander Turenko]

I'm going to archive the repository. I'll proceed as follows:

• Mark all open pull requests with the archived label and close.
• Mark all open issues with archived and wontfix labels and close.
• Archive the repository.

Consider the following projects:

• https://github.com/tarantool/graphql
• https://github.com/tarantool/graphqlapi
• https://github.com/tarantool/graphqlide