Remove usage of GREP_OPTIONS (deprecated)

zsh/zshrc

@@ -127,8 +127,7 @@ alias rm='rm -i'
 alias mv='mv -i'
 alias cp='cp -i'
 
-export GREP_OPTIONS="--color=auto"
-alias mgrep="grep -rnisH"
+alias mgrep="grep --color=auto -rnisH"
 
 alias rsu="sudo -E zsh"
 alias reloadsh="exec zsh"