bpo-43762: Add audit events for loading of sqlite3 extensions

[erlend-aasland]

https://bugs.python.org/issue43762

[erlend-aasland]

cc. @tiran

[erlend-aasland]

@tiran & @zooba, can one of you review this? FYI, the previous sqlite3 audit events were added in #14301 by Steve.

[zooba]

Couple of minor tweaks, mainly for readability/ease of use.

I wonder if it's worth returning the connection object when it's created (through a new event in module.c) and then reference it in these events? That can then correlate these (and other) events with the file - we do this already for sockets.

After some thought, I think it's probably not worth it for these ones. The important information is in the extension being loaded, and it doesn't really relate to the connection at all. However, if we wanted to add it later, we couldn't. So might be worth doing now?

[erlend-aasland]

FYI, rebased onto main to resolve conflicts.

[zooba]

Approved with the doc update suggestions

[erlend-aasland]

Approved with the doc update suggestions

Thanks for reviewing! BTW, I used /handle iso. /result (ctypes uses that already). I figured it aligned better with the SQLite jargon.