fix: fixes SQLITE not respecting orderby + limit on update

[GiovaniGuizzo]

Checklist for Pull Requests

• All tests pass (yarn test:all and yarn test:integration)
• Code follows the style guide and passes lint checks
• Documentation is updated (README, docs, etc)
• Linked to corresponding issue, if applicable

Summary of Changes

Closes #159

Apparently, SQLite does not respect updates with order by and limit. For it do be able to do so, one must enable SQLITE_ENABLE_UPDATE_DELETE_LIMIT during compilation time. For what is worth, better-sqlite3 has this option enabled, but it doesn't work.

I have added a very important missing test case where we assert whether claimPendingJob claims only the quantity passed. It works on all dbs, except SQLite. I tried using both sqlite3 and better-sqlite3, none worked.

An alternative solution would be for us to compile our own version of SQLite, but I'd rather not.

This solution that I cam up with is not perfect, but it gets the job done. We first select the jobs to update, then update them in a second instruction. In a race condition, we might have a job being claimed by two different workers, but I kept the status = waiting clause in the query to avoid that race condition.