Avoid infinite loop in case where `pwd` returns relative path
Avoid infinite loop in case where `pwd` returns relative path

The `pwd` may return relative path if the `$PWD` is badly declared
in bash/zsh (e.g. `PWD="." bash`). To avoid the infinite loop in
`find_local_version_file()`, stop finding the version file if the
target paths are same consecutively.

obimod/pyenv,syndbg/goenv,chenfengyuan/pyenv,lepture/pyenv,habinmusic/pyenv,dongguangming/pyenv,UCASREN/pyenv,lozybean/pyenv,pyenv/pyenv,syndbg/goenv,kevinburke/pyenv,rowhit/pyenv,habinmusic/pyenv,dnsd/pyenv,xshwy/pyenv,takluyver/pyenv,VShangxiao/pyenv,sebhahn/pyenv,BanzaiMan/pyenv,genome-vendor/pyenv,kevinburke/pyenv,recruit-mtl/pyenv,syndbg/goenv,fly19890211/pyenv,hlecuanda/pyenv,cehoffman/pyenv,hlecuanda/pyenv,fly19890211/pyenv,VShangxiao/pyenv,yyuu/pyenv,yeonsh/pyenv,rowhit/pyenv,pyenv/pyenv,recruit-mtl/pyenv,cehoffman/pyenv,sebhahn/pyenv,dnsd/pyenv,blueyed/pyenv,genome-vendor/pyenv,zmwangx/pyenv,takluyver/pyenv,sebhahn/pyenv,pyenv/pyenv,xshwy/pyenv,syndbg/goenv,chenfengyuan/pyenv,dongguangming/pyenv,obimod/pyenv,yeonsh/pyenv,yyuu/pyenv,lepture/pyenv,lozybean/pyenv,BanzaiMan/pyenv,zmwangx/pyenv,UCASREN/pyenv