closes bpo-31525: require sqlite3_prepare_v2

[benjaminp]

This is based on
ghaering/pysqlite@40b349c#diff-0489411409cd2934730e88bf7767790,
though I believe we can be a bit more aggressive about deleting code.

https://bugs.python.org/issue31525

[berkerpeksag]

We can also delete the following snippet from Modules/_sqlite/util.c:

#if SQLITE_VERSION_NUMBER < 3003009
    /* SQLite often doesn't report anything useful, unless you reset the statement first.
       When using sqlite3_prepare_v2 this is not needed. */
    if (st != NULL) {
        (void)sqlite3_reset(st);
    }
#endif

Could you also note the minimum SQLite version in the blurb entry?

[berkerpeksag]

This looks pretty good to me except 2-space indentation in Modules/_sqlite/cursor.c.