Indeed, the database/sql package ensures that sqlite connections are
used only by on goroutine at a time.
The timeout has been increased to make go-sql-test passed.

When specifying SQLITE_TRANSIENT, SQLite makes a copy of the string
so we can pass directly a pointer when calling sqlite3_bind_text/
sqlite3_result_text.
On the other hand, when loading blobs with sqlite3_column_bytes/
sqlite3_value_bytes, we must make a copy.