docs: Update TBS perf numbers after improvements

[carsonip]

Update https://www.elastic.co/docs/solutions/observability/apm/transaction-sampling#_tail_based_sampling_performance_and_requirements

TODO

• Change section from 9.0 to 9.0.3 to be specific and because it contains significant perf improvements for larger instances (PR: TBS: Optimize performance for instances with more CPU and memory #17254)
• Update deployment template to use ARM CPU Optimized for AWS because the x86 CPU optimized option is not available on ECH UI