fix(ci_visibility): get default environment from agent when DD_ENV is not set

[romainkomorndatadog]

This fixes an issue where, if we are in EVP mode, and the agent has a custom default environment set (eg: using DD_APM_ENV), but DD_ENV is not set in the environment, we would incorrectly set the environment to None.

Instead, we now query the agent's info page and use the config.default_env key to choose the environment value.

In somewhat-related changes, we now also explicitly default the environment to "none" in agentless mode if it is not set by the user, whereas before we would use a None value which would serialize to null, and we would rely on the backend to perform the null -> "none" change. Since the backend was already enforcing this behavior, it should be a no-op from the user's perspective.

Checklist

• PR author has checked that all the criteria below are met
• The PR description includes an overview of the change
• The PR description articulates the motivation for the change
• The change includes tests OR the PR description describes a testing strategy
• The PR description notes risks associated with the change, if any
• Newly-added code is easy to change
• The change follows the library release note guidelines
• The change includes or references documentation updates if necessary
• Backport labels are set (if applicable)

Reviewer Checklist

• Reviewer has checked that all the criteria below are met
• Title is accurate
• All changes are related to the pull request's stated goal
• Avoids breaking API changes
• Testing strategy adequately addresses listed risks
• Newly-added code is easy to change
• Release note makes sense to a user of the library
• If necessary, author has acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment
• Backport labels are set in a manner that is consistent with the release branch maintenance policy

[github-actions]

CODEOWNERS have been resolved as:

releasenotes/notes/ci_visibility-get_agent_default_env-bf4a11283dccdf87.yaml  @DataDog/apm-python
ddtrace/internal/ci_visibility/recorder.py                              @DataDog/ci-app-libraries
tests/ci_visibility/api_client/test_ci_visibility_api_client.py         @DataDog/ci-app-libraries

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 31.25000% with 11 lines in your changes missing coverage. Please review.

Project coverage is 3.60%. Comparing base (74e3d51) to head (6b6e97c).

Files with missing lines	Patch %	Lines
ddtrace/internal/ci_visibility/recorder.py	31.25%	11 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #11478       +/-   ##
===========================================
- Coverage   14.09%    3.60%   -10.50%     
===========================================
  Files        1536     1487       -49     
  Lines      133599   128946     -4653     
===========================================
- Hits        18829     4643    -14186     
- Misses     114770   124303     +9533     

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[romainkomorndatadog]

/merge

[dd-devflow]

Devflow running: /merge

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2024-11-21 13:37:43 UTC ℹ️ MergeQueue: waiting for PR to be ready

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2024-11-21 14:21:43 UTC ℹ️ MergeQueue: merge request added to the queue

The median merge time in main is 35m.

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2024-11-21 21:42:02 UTC ⚠️ MergeQueue: This merge request build was cancelled

This merge request build was cancelled

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-11-21 14:19:21

Comparing candidate commit cc649bc in PR branch romain.komorn/chore/fix_env_in_evp_proxy_cases with baseline commit 74e3d51 in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 388 metrics, 2 unstable metrics.