release: Finish preparation for 4.11.2

release: updated pip2nix output for 4.11.2

release: Start preparation for 4.11.2

subprocessio: use safe b.read() and prevent potential valueErrors

subprocess: use subprocessio helper to run various subprocess commands.

git: use subprocessio for hooks execution to use non-blocking subprocess.

http: status will return PID to help check stuck workers.

subprocessio: use safe b.read() and prevent potential valueErrors

subprocess: use subprocessio helper to run various subprocess commands.

git: use subprocessio for hooks execution to use non-blocking subprocess.