Remove zsh `jj` keybinding
Remove zsh `jj` keybinding

As reported in #405, the `jj` keybinding is problematic for some users
as it enters vi-mode whenever a user types a string that actually
contains two consecutive `j`s.

While consecutive `j`s are unusual in English, usernames with
consecutive `j`s such as that of the contributor who reported the
problem (@jjlangholtz) are common enough that we shouldn't force this
mapping on users.

Users can add their own keybinding to their local configuration or use
the already-provided `Esc` binding to enter vi-mode.

PR #405 contains other keybinding changes that we don't want to apply,
this commit addresses only the `jj` binding.

YepengFan/dotfiles,toobulkeh/dotfiles,Danielpk/dotfiles,voanhduy1512/dotfiles,bigbam505/dotfiles-work,secoast00/dotfiles,T1D/dotfiles,Thau/dotfiles,ncuesta/dotfiles,Thau/dotfiles,revgum/dotfiles,koerbcm/dotfiles,alexbaldwin/dotfiles,ncuesta/dotfiles,aliceyoung9/dotfiles,lannn/dotfiles,firmanm/dotfiles,ransingh/dotfiles,mspringfield/dotfiles,astoellis/dotfiles,Danielpk/dotfiles,robkilby/dotfiles,ren/dotfiles,kkelleey/dotfiles,voanhduy1512/dotfiles,Jon-Long/dotfiles,hythyt9898/dotfiles,ransingh/dotfiles,aliceyoung9/dotfiles,mspringfield/dotfiles,ren/dotfiles,garrettd714/dotfiles,ZloeSabo/dotfiles,bigbam505/dotfiles-work,koerbcm/dotfiles,Jaicob/dotfiles,yeuem1vannam/dotfiles,lannn/dotfiles,kkelleey/dotfiles,tchiarato/dotfiles,bschmoker/dotfiles,ajkamel/dotfiles,prabinv/dotfiles,T1D/dotfiles,bschmoker/dotfiles,revgum/dotfiles,ransingh/dotfiles,koerbcm/dotfiles,moofish32/dotfiles,ajkamel/dotfiles,tsigo/dotfiles-thoughtbot,koerbcm/dotfiles,firmanm/dotfiles,secteur0/dotfiles,rootulp/dotfiles,YepengFan/dotfiles,rootulp/dotfiles,timgremore/dotfiles,secteur0/dotfiles,ncepuwanghui/dotfiles,ncepuwanghui/dotfiles,Jaicob/dotfiles,Jiwoong/dotfiles,yeuem1vannam/dotfiles,ecnalyr/dotfiles,Jon-Long/dotfiles,koerbcm/dotfiles,timgremore/dotfiles,astoellis/dotfiles,ZloeSabo/dotfiles,Jiwoong/dotfiles,soon0009/thoughtbot-dotfiles,tchiarato/dotfiles,turino/dotfiles,dainmiller/thoughtbot-dotfile-mods,dainmiller/thoughtbot-dotfile-mods,hythyt9898/dotfiles,soon0009/thoughtbot-dotfiles,prabinv/dotfiles,moofish32/dotfiles,garrettd714/dotfiles