ci: iast unvendor pybind11 (with build requirement)

[gnufede]

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/appsec/_iast/_taint_tracking/CMakeLists.txt                     @DataDog/asm-python
ddtrace/appsec/_iast/_taint_tracking/tests/CMakeLists.txt               @DataDog/asm-python
hatch.toml                                                              @DataDog/python-guild
mypy.ini                                                                @DataDog/python-guild @DataDog/apm-core-python
pyproject.toml                                                          @DataDog/python-guild
scripts/cformat.sh                                                      @DataDog/apm-core-python
scripts/cppcheck.sh                                                     @DataDog/apm-core-python
setup.cfg                                                               @DataDog/python-guild

[github-actions]

Bootstrap import analysis

Comparison of import times between this PR and base.

Summary

The average import time from this PR is: 276 ± 4 ms.

The average import time from base is: 278 ± 4 ms.

The import time difference between this PR and base is: -2.4 ± 0.2 ms.

Import time breakdown

The following import paths have shrunk:

ddtrace.auto 2.060 ms (0.75%)

ddtrace.bootstrap.sitecustomize 1.385 ms (0.50%)

ddtrace.bootstrap.preload 1.385 ms (0.50%)

ddtrace.internal.remoteconfig.client 0.665 ms (0.24%)

ddtrace 0.675 ms (0.24%)

ddtrace.internal._unpatched 0.031 ms (0.01%)

json 0.031 ms (0.01%)

json.decoder 0.031 ms (0.01%)

re 0.031 ms (0.01%)

enum 0.031 ms (0.01%)

types 0.031 ms (0.01%)