ddtrace/tracer: added W3C tracecontext extract benchmark

[dianashevchenko]

What does this PR do?

This PR adds BenchmarkExtractW3C, in line with having BenchmarkExtractDatadog.
Benchmarks reports increased resource usage compared to Datadog propagator. Similar behaviour is observed in Inject method benchmark

BenchmarkExtractDatadog-10       4332901               293.8 ns/op           349 B/op          5 allocs/op
BenchmarkExtractW3C-10            799790              1511 ns/op            1040 B/op         18 allocs/op

BenchmarkInjectDatadog-10        1560982               754.6 ns/op           296 B/op          7 allocs/op
BenchmarkInjectW3C-10              92199             12750 ns/op            4027 B/op        247 allocs/op

Motivation

Describe how to test/QA your changes

Reviewer's Checklist

• Changed code has unit tests for its functionality.
• If this interacts with the agent in a new way, a system test has been added.

[pr-commenter]

Benchmarks

Benchmark execution time: 2023-06-26 16:00:18

Comparing candidate commit a55d619 in PR branch shevchenko/benchmark-w3c-extract with baseline commit ea87357 in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 24 metrics, 0 unstable metrics.

[ahmed-mez]

Let's add the new test to the benchmarking platform as documented here!

[dianashevchenko]

Let's add the new test to the benchmarking platform as documented here!

Note that your new benchmark must already exist in the main branch, for that reason it is best for new benchmarks to be added in their own PR and a second PR opened afterwards to add them to the PR benchmark script.