Remote library configuration support and ITR::Runner

[anmarchenko]

What does this PR do?

First step for Intelligent Test Runner implementation: implement remote library settings configuration

Main changes:

• Agentless and EvpProxy api clients support multiple backend endpoints now (citestcycle-intake.dd-site for events and api.dd-site for remote configuration)
• RemoteSettingsApi client for fetching the remote configuration
• Datadog::CI::ITR::Runner class that holds ITR configuration
• Some ITR related tags for test_session_end events: test.code_coverage.enabled, test.itr.tests_skipping.enabled, test.itr.tests_skipping.type
• when ITR is enabled in local settings, TestVisibility::Recorder fetches remote settings and configures ITR

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 99.08%. Comparing base (8eb9540) to head (86932a8).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #129 +/- ## ========================================== + Coverage 99.02% 99.08% +0.05% ========================================== Files 152 156 +4 Lines 6672 7102 +430 Branches 299 303 +4 ========================================== + Hits 6607 7037 +430 Misses 65 65 ```

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