Implement a workaround for Full joins in SQLite

[wdanilo]

This task is automatically imported from the old Task Issue Board and it was originally created by Radosław Waśko.
Original issue is here.

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SQLite does not support Right and Full joins.

We have a simple workaround for Right joins which swaps the order and does a left join instead.

For Full joins it is a bit more complicated - we need to do a left join and a right anti-join and then union them.

We should be able to generate a query along the lines of https://stackoverflow.com/a/1923306

The same workaround may be necessary for PostgreSQL, at least when the join condition is more complex, as for non-hashable join conditions regular FULL OUTER JOIN sometimes fails with TODO Turns out this issue was due to a COALESCE present due to null handling. For reasonably simple expressions the full join works without issue.

Blockers:

[#184215302 - Table.union for Database is best implemented before this task is attempted (no ticket yet, currently only for In-Memory)](https://www.pivotaltracker.com/story/show/#184215302 - Table.union for Database is best implemented before this task is attempted (no ticket yet, currently only for In-Memory)) blocked

• Add Table.union to the Database Table. #5235

[enso-bot]

Radosław Waśko reports a new STANDUP for yesterday (2023-04-06):

Progress: Removed the Full Join workaround and re-enable Full join tests in SQLite - bumped version supports it out of the box. Merged the PR. Started a Discussion on static call issues. Updated the println fix PR. Started work on adding missing typechecks to column operations. It should be finished by 2023-04-06.

Next Day: Next day I will be working on the #6106 task. Continue work on column typechecks.