[3.11] gh-105375: Explicitly initialise all {Pickler,Unpickler}Object fields (#105686)#105711

kumaraditya303 merged 2 commits intopython:3.11python/cpython:3.11from

erlend-aasland:backport-3.11-fix-pickle-newgcobjerlend-aasland/cpython:backport-3.11-fix-pickle-newgcobjCopy head branch name to clipboard