test(debugger): ensure span error budgets are reasonable

[tylfin]

Motivation

Add a test to verify that span decoration probes with improper expressions (e.g., "Cannot dereference field") have their error logs rate-limited to at most once per second. Currently marked as a bug for Java since span decoration probes lack probe budgets, producing 150 error snapshots for 150 requests instead of the expected ~1 per second.

Changes

• Added a new test method test_span_probe_expression_budgets in tests/debugger/test_debugger_probe_budgets.py to verify that error logs from span probe expression failures are rate-limited to at most 1 per second, with appropriate assertions and handling for language-specific limitations.
• Introduced a helper method setup_span_probe_expression_budgets to configure and trigger the span probe expression budget scenario in the same test file.
• Added a new probe configuration file probe_span_method_budgets_expression.json under tests/debugger/utils/probes/ to define a span probe with an intentionally failing expression, used for testing error logging and rate limiting.
• Imported the bug decorator from utils in tests/debugger/test_debugger_probe_budgets.py to allow marking tests with known bugs, specifically for Java.

Workflow

1. ⚠️ Create your PR as draft ⚠️
2. Work on you PR until the CI passes
3. Mark it as ready for review
   • Test logic is modified? -> Get a review from RFC owner.
   • Framework is modified, or non obvious usage of it -> get a review from R&P team

🚀 Once your PR is reviewed and the CI green, you can merge it!

🛟 #apm-shared-testing 🛟

Reviewer checklist

• Anything but tests/ or manifests/ is modified ? I have the approval from R&P team
• A docker base image is modified?
  • the relevant build-XXX-image label is present
• A scenario is added, removed or renamed?
  • Get a review from R&P team

[github-actions]

CODEOWNERS have been resolved as:

tests/debugger/utils/probes/probe_span_method_budgets_expression.json   @DataDog/debugger @DataDog/system-tests-core
manifests/dotnet.yml                                                    @DataDog/apm-dotnet @DataDog/asm-dotnet
manifests/java.yml                                                      @DataDog/asm-java @DataDog/apm-java
manifests/php.yml                                                       @DataDog/apm-php @DataDog/asm-php
manifests/python.yml                                                    @DataDog/apm-python @DataDog/asm-python
tests/debugger/test_debugger_probe_budgets.py                           @DataDog/debugger @DataDog/system-tests-core

[nccatoni]

LGTM for @DataDog/system-tests-core, you should also get a review from someone familiar with the feature

[datadog-official]

✅ Tests

🎉 All green!

❄️ No new flaky tests detected
🧪 All tests passed

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[daniel-romano-DD]

LGTM