Adding the ability to disable TraceContext header injection

[eyalkoren]

What does this PR do?

Adding the ability to disable TraceContext headers on outgoing requests.
An example for when this may be useful is described in a forum topic

Checklist

• This is an enhancement of existing features, or a new feature in existing plugins
  • I have updated CHANGELOG.asciidoc
  • I have added tests that prove my fix is effective or that my feature works
  • Added an API method or config option? Document in which version this will be introduced
  • I have made corresponding changes to the documentation

[apmmachine]

💚 Build Succeeded

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Build stats

• Start Time: 2023-01-31T16:16:04.466+0000

• Duration: 58 min 54 sec

Test stats 🧪

Test	Results
Failed	0
Passed	3483
Skipped	43
Total	3526

💚 Flaky test report

Tests succeeded.

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