Migrate script batch time interval smaller than expected

[mtheck]

timescaledb-extras/migrate.sql

Lines 119 to 120 in 52443a4

	-- convert the passed in interval to microseconds
	SELECT EXTRACT(epoch from batch_time)*100000 into interval_internal;

The conversion of the batch time interval as epoch to microseconds uses a multiplication by 1e5 instead of 1e6.