Reduce DCR minCapacity to 27 instead of 25

@jacobwinch made a good point in the review about dropping the capacity in groups of 3 and monitoring at each stage. It's good to modify ASG capacity in groups of 3 so that AWS can evenly distribute across Availability Zones (https://docs.aws.amazon.com/autoscaling/ec2/userguide/auto-scaling-benefits.html#arch-AutoScalingMultiAZ).

#9369 (comment)

Co-authored-by: Jacob Winch <[email protected]>

dotcom-rendering/cdk/bin/cdk.ts

@@ -13,7 +13,7 @@ new DotcomRendering(app, 'DotcomRendering-PROD', {
 	...sharedProps,
 	app: 'rendering',
 	stage: 'PROD',
-	minCapacity: 25,
+	minCapacity: 27,
 	maxCapacity: 120,
 	instanceType: 't4g.small',
 });