Update Datadog SDK to 2.18.0

[0xnm]

What does this PR do?

This PR updates Datadog SDK to 2.18.0.

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Make sure you discussed the feature or bugfix with the maintaining team in an Issue
• Make sure each commit and the PR mention the Issue number (cf the CONTRIBUTING doc)

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.00%. Comparing base (6eaa3cd) to head (b8d8429).
Report is 2 commits behind head on develop.

Additional details and impacted files

@@              Coverage Diff              @@
##             develop     #310      +/-   ##
=============================================
- Coverage      78.21%   78.00%   -0.21%     
+ Complexity       261      260       -1     
=============================================
  Files             31       31              
  Lines            941      941              
  Branches         113      113              
=============================================
- Hits             736      734       -2     
  Misses           151      151              
- Partials          54       56       +2     

see 2 files with indirect coverage changes