Merge pull request #3930 from HeidiSteen/release-azs-5

Tier doc update (add bullet for tier considerations)

Author: prmerger-automator[bot]

articles/search/search-sku-tier.md

@@ -21,6 +21,7 @@ The tier determines the:
 + Maximum number of indexes and other objects allowed on the service.
 + Size and speed of partitions (physical storage).
 + Billable rate as a fixed monthly cost, but also an incremental cost if you add capacity.
++ Workload characteristics. Some tiers are optimized for specific workloads.
 
 In a few instances, the tier you choose determines the availability of [premium features](#feature-availability-by-tier).