Add benchmark tests

[martinkuba]

This is a tracking issue for adding benchmark tests to measure and track performance of the JS SDK.

The goal is to add performance benchmark tests, and make the results consistent and visible. This is part of a cross-language effort.

Tasks:

• add a benchmark test as a starting point and template for others
  Introduce benchmark tests #4105
• add a Github Actions workflow to run the tests automatically
  Benchmark tests workflow #4144
• get access to the shared self-hosted runner for the workflow
  REQUEST: Repository maintenance on opentelemetry-js community#1701
• publish results to Github Pages
• Add documentation on how to contribute benchmark tests
  Added performance benchmarking doc #4169
• update results web page to match the OTel theme (similar to Collector benchmarks)
  Update benchmarks page theme #4176
• add results to the OTel website (similar to Collector benchmarks)
  Add page for JS benchmarks opentelemetry.io#3342

[pichlermarc]

Looks like it's all merged now, thanks for all the work @martinkuba 🙂
I this issue good to close? 🙂