Make Gemnasium analyzer use embedded database for vulnerabilities instead of yml files

Summary

We are moving Gemnasium analyzer towards making use of gemnasium-db repo instead of api to find vulnerabilities. As part of #14630 (comment 221764383) we should consider using embedded database instead of using yml files. We could extract parts of gemnasium-db insert into db and ship container with it. For example, for gemnasium-python we can only take https://gitlab.com/gitlab-org/security-products/gemnasium-db/tree/master/pypi insert into db system and ship container with it.

Improvements

It will be more performant for search and read operations

Risks

DB won't be as flexible as yml. We could add fields to yml but if we have established db model with multiple tables it might take more time to make some changes.

Involved components

Gemnasium analyzers