pw_env_setup: Roll the Python protobuf package to 7.36.2

Updates the Python environment from protobuf 6.33.5 to 7.36.2, with
related uprevs to other Python packages that needed to match. The
constraint and lock files are updated to match.

The Bazel deps for protobuf et al are NOT rolled, to give a window for
downstream projects to roll their bazel deps without build breakage, as
it is not possible to build with a newer protoc version (controlled by
the bazel_dep and/or CIPD configuration) before this change lands, but
it is after.

The followup to update Pigweed's bazel_deps will follow.

Python packages updated:
- protobuf: 6.33.5 -> 7.36.2
- mypy-protobuf: 3.7.0 -> 5.1.0
- types-protobuf: 6.32.1.20251210 -> 7.34.1.20260518
- googleapis-common-protos: 1.70.0 -> 1.75.0
- google-api-core: 2.29.0 -> 2.33.0
- proto-plus: 1.27.1 -> 1.28.2
- requests: 2.32.5 -> 2.33.0
- certifi: 2021.10.8 -> 2024.12.14

Additional Python changes to resolve mypy checks after this roll:
- pw_tokenizer/py/pw_tokenizer/proto/__init__.py
- pw_rpc/py/pw_rpc/descriptors.py
- pw_build/py/pw_build/workflows/build_driver.py

NO_IFTTT=Intentional two-stage roll (Python wheel preroll before Bazel/CIPD roll)

Bug: 531678426
Test: Presubmit
Change-Id: I803884c0c20c65b0c8d782da01bf886c796d0182
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/478565