Create a sample demonstrating LLMRateLimitingPlugin and RateLimitingPlugin together

[waldekmastykarz]

After implementing #1309, create a new sample that demonstrates the use of both LLMRateLimitingPlugin and the regular RateLimitingPlugin together. The sample should simulate realistic throttling scenarios that developers might encounter when using LLMs in production, showcasing how to combine these plugins for effective rate limiting and throttling management.