fix: remove extra bound argument in BigQuery InsertMigration (#817)

`InsertMigration` in the BigQuery driver interpolates `version` into the
SQL string, then also passes it to `db.Exec` as a bound argument. The
query has no placeholders, so the argument has nothing to bind to. Real
BigQuery silently ignores it, but newer versions of
goccy/bigquery-emulator reject the insert:

```
googleapi: Error 400: failed to exec INSERT INTO ... : sql: expected 0 arguments, got 1
```

This makes `dbmate up` fail against the emulator right after applying
the first migration. `DeleteMigration` does the same interpolation
without the extra argument, so this looks like a leftover from #523.

Following review, both `InsertMigration` and `DeleteMigration` now bind
`version` as a query parameter instead of interpolating it into the SQL,
and `InsertMigration` runs on the transaction `Migrate()` passes in (as
`DeleteMigration` already did).

Tested the `pkg/driver/bigquery` suite against emulator 0.4.4 (the
version pinned in docker-compose.yml, which tolerates the extra arg) and
0.8.1 (which rejects it) - passes on both. CI doesn't catch this today
because it pins 0.4.4; happy to bump the image here or in a follow-up if
you want the regression covered.

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>