[Performance] distributed deployments of NightHawk to enable distributed performance tests

Current Behavior

Right now performance tests using NightHawk are limited to single instance load generation. This limits the amount of traffic that can be generated to the output of the single machine that the benchmark tool runs on in or out of a cluster.

Desired Behavior

Support distributed deployments of NightHawk to enable users to run distributed performance tests to better mimic real-world, distributed systems scenarios.

Resources

Proposed design spec: https://docs.google.com/document/d/1_hhQ5w1iLClgf7RvboI6il-eMKKAVPwz50GHm2VN4Bg/edit#heading=h.3tnqdf3a6jei

Additional Context
Load generators and meshery: https://docs.meshery.io/extensibility/load-generators
Performance management in meshery: https://docs.meshery.io/functionality/performance-management

Contributor Resources

• See the Contributing to getnighthawk.dev Website
• See the Project Site section of GetNighthawk project doc

Start with the proposed design spec, then read the Load generators and Meshery and Performance management resources linked in the issue. Compare those expectations with NightHawk's current single-instance load generation. Done means users can deploy NightHawk in a distributed setup and run distributed performance tests.