chore(pin): remove all deprecated references [3.0]

[mabdinur]

Motivation

Ensure deprecation warnings are only logged when users manually use deprecated interfaces.

Description

This change ensures we do not use the deprecated ddtrace.Pin reference in docs and integrations.

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/__init__.py                                                     @DataDog/apm-core-python
ddtrace/contrib/aredis/__init__.py                                      @DataDog/apm-core-python @DataDog/apm-idm-python
ddtrace/contrib/httpx/__init__.py                                       @DataDog/apm-core-python @DataDog/apm-idm-python
ddtrace/contrib/internal/mongoengine/trace.py                           @DataDog/apm-core-python @DataDog/apm-idm-python
ddtrace/contrib/internal/pylibmc/client.py                              @DataDog/apm-core-python @DataDog/apm-idm-python
ddtrace/contrib/internal/pymongo/client.py                              @DataDog/apm-core-python @DataDog/apm-idm-python
ddtrace/contrib/internal/tornado/application.py                         @DataDog/apm-core-python @DataDog/apm-idm-python
ddtrace/contrib/redis/__init__.py                                       @DataDog/apm-core-python @DataDog/apm-idm-python
ddtrace/contrib/yaaredis/__init__.py                                    @DataDog/apm-core-python @DataDog/apm-idm-python
docs/api.rst                                                            @DataDog/python-guild

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: munir/remove-deprecated-code-from-integratios
Commit report: 36bc707
Test service: dd-trace-py

✅ 0 Failed, 130 Passed, 1468 Skipped, 4m 26.01s Total duration (35m 35.15s time saved)