feat(azure_functions): add tracing support for timer triggers

[duncanpharvey]

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:

ddtrace/contrib/internal/azure_functions/utils.py                       @DataDog/apm-core-python @DataDog/apm-idm-python
releasenotes/notes/feat-azure-functions-timer-trigger-f47914ec46fc30ca.yaml  @DataDog/apm-python
tests/snapshots/tests.contrib.azure_functions.test_azure_functions_snapshot.test_timer.json  @DataDog/apm-python
.gitlab/services.yml                                                    @DataDog/python-guild @DataDog/apm-core-python
ddtrace/_trace/trace_handlers.py                                        @DataDog/apm-sdk-api-python
ddtrace/contrib/internal/azure_functions/patch.py                       @DataDog/apm-core-python @DataDog/apm-idm-python
docker-compose.yml                                                      @DataDog/apm-core-python
tests/contrib/azure_functions/azure_function_app/function_app.py        @DataDog/apm-core-python @DataDog/apm-idm-python
tests/contrib/azure_functions/azure_function_app/local.settings.json    @DataDog/apm-core-python @DataDog/apm-idm-python
tests/contrib/azure_functions/test_azure_functions_snapshot.py          @DataDog/apm-core-python @DataDog/apm-idm-python
tests/contrib/suitespec.yml                                             @DataDog/apm-core-python @DataDog/apm-idm-python

[github-actions]

Bootstrap import analysis

Comparison of import times between this PR and base.

Summary

The average import time from this PR is: 232 ± 4 ms.

The average import time from base is: 235 ± 3 ms.

The import time difference between this PR and base is: -3.1 ± 0.2 ms.

Import time breakdown

The following import paths have shrunk:

ddtrace.auto 2.074 ms (0.90%)

ddtrace.bootstrap.sitecustomize 1.409 ms (0.61%)

ddtrace.bootstrap.preload 1.409 ms (0.61%)

ddtrace.internal.products 1.409 ms (0.61%)

ddtrace.internal.remoteconfig.client 0.657 ms (0.28%)

ddtrace 0.665 ms (0.29%)

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-04-04 19:22:01

Comparing candidate commit 3bb23b8 in PR branch duncan-harvey/azure-functions-timer-trigger with baseline commit 55aaf72 in branch main.

Found 3 performance improvements and 0 performance regressions! Performance is the same for 495 metrics, 2 unstable metrics.

scenario:flasksqli-appsec-enabled

• 🟩 execution_time [-183.027µs; -172.608µs] or [-7.909%; -7.459%]

scenario:flasksqli-iast-enabled

• 🟩 execution_time [-179.927µs; -169.212µs] or [-7.783%; -7.319%]

scenario:flasksqli-tracer-enabled

• 🟩 execution_time [-189.831µs; -179.095µs] or [-8.202%; -7.738%]