Fix preview when log message contains hash-like string (#13)

fzf-git.sh

@@ -177,9 +177,9 @@ _fzf_git_hashes() {
     --prompt '🍡 Hashes> ' \
     --header $'CTRL-O (open in browser) ╱ CTRL-D (diff) ╱ CTRL-S (toggle sort)\n\n' \
     --bind "ctrl-o:execute-silent:bash $__fzf_git commit {}" \
-    --bind 'ctrl-d:execute:grep -o "[a-f0-9]\{7,\}" <<< {} | xargs git diff > /dev/tty' \
+    --bind 'ctrl-d:execute:grep -o "[a-f0-9]\{7,\}" <<< {} | head -n 1 | xargs git diff > /dev/tty' \
     --color hl:underline,hl+:underline \
-    --preview 'grep -o "[a-f0-9]\{7,\}" <<< {} | xargs git show --color=always' "$@" |
+    --preview 'grep -o "[a-f0-9]\{7,\}" <<< {} | head -n 1 | xargs git show --color=always' "$@" |
   grep -o "[a-f0-9]\{7,\}"
 }