feat(django): add dbm trace propagation for django postgres

[wconti27]

Closes: #8239

This PR implements DBM trace propagation for postgres database usage through django.

Checklist

• Change(s) are motivated and described in the PR description
• Testing strategy is described if automated tests are not included in the PR
• Risks are described (performance impact, potential for breakage, maintainability)
• Change is maintainable (easy to change, telemetry, documentation)
• Library release note guidelines are followed or label changelog/no-changelog is set
• Documentation is included (in-code, generated user docs, public corp docs)
• Backport labels are set (if applicable)
• If this PR changes the public interface, I've notified @DataDog/apm-tees.

Reviewer Checklist

• Title is accurate
• All changes are related to the pull request's stated goal
• Description motivates each change
• Avoids breaking API changes
• Testing strategy adequately addresses listed risks
• Change is maintainable (easy to change, telemetry, documentation)
• Release note makes sense to a user of the library
• 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

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-06-27 16:14:19

Comparing candidate commit 8ba3a04 in PR branch conti/fix-django-dbm-propagation with baseline commit f86e1ef in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 221 metrics, 9 unstable metrics.

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: conti/fix-django-dbm-propagation
Commit report: 535b535
Test service: dd-trace-py

✅ 0 Failed, 130365 Passed, 46266 Skipped, 6h 10m 26.1s Total duration (4h 23m 31.41s time saved)

[brettlangdon]

adding @emmettbutler to review the changes I made to core API.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 12.50000% with 161 lines in your changes missing coverage. Please review.

Project coverage is 10.16%. Comparing base (4acfde7) to head (8ba3a04).
Report is 2 commits behind head on main.

Files	Patch %	Lines
tests/contrib/shared_tests_async.py	0.00%	54 Missing ⚠️
tests/contrib/django/test_django_dbm.py	0.00%	51 Missing ⚠️
tests/contrib/shared_tests.py	0.00%	23 Missing ⚠️
ddtrace/internal/core/event_hub.py	0.00%	11 Missing ⚠️
tests/utils.py	31.25%	11 Missing ⚠️
ddtrace/propagation/_database_monitoring.py	45.45%	6 Missing ⚠️
ddtrace/contrib/django/patch.py	83.33%	2 Missing ⚠️
ddtrace/settings/integration.py	75.00%	1 Missing ⚠️
tests/contrib/aiomysql/test_aiomysql.py	0.00%	1 Missing ⚠️
tests/contrib/pymysql/test_pymysql.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #9601       +/-   ##
===========================================
- Coverage   74.65%   10.16%   -64.49%     
===========================================
  Files        1381     1351       -30     
  Lines      127965   126079     -1886     
===========================================
- Hits        95531    12819    -82712     
- Misses      32434   113260    +80826     

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[brettlangdon]

question, otherwise lgtm

[emmettbutler]

The core changes make sense to me

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: conti/fix-django-dbm-propagation
Commit report: 8ba3a04
Test service: dd-trace-py

✅ 0 Failed, 118418 Passed, 58274 Skipped, 4h 31m 23.96s Total duration (5h 21m 11.37s time saved)