fix: bigint as primary key

[Vakrim]

This PR adds bigint as acceptable type of isPrimaryKey.

I was following https://mikro-orm.io/docs/using-bigint-pks recipe, but saw that update queries were missing where clause when using bigint as PK.

I've pinpointed issue to those lines that doesn't prepare correct where object for knex when where is of bigint type.

mikro-orm/packages/knex/src/AbstractSqlDriver.ts

Lines 270 to 272 in c0c658e

	if (Utils.isPrimaryKey(where) && pks.length === 1) {
	where = { [pks[0]]: where } as FilterQuery<T>;
	}