If you're using the original hardware, there is no need for any antiseize lubricant to prevent corrosion because the bolts are coated with an anticorrosive material.
Thread locker is not required nor recommended for the tensioner bolt.
Now, if you expect the bolt holding the tensioner to the engine to be removed and replaced a number of times in the future, I'd use antiseize which is good to use as a lubricant on any fastener which is frequently removed and replaced. But, again, if you're not going to be removing the tensioner again and again, you don't need any lubricant.
Torque the bolt to 24 lb/ft. Reduce that by 10-15% if you elect to use antiseize.