How to unstage a specific file from your last commit ?

git.txt

[arup@critique (permitted_user_fix_review)]$ git commit -m "Live update of notification counter after create/remove any reviews"
# On branch permitted_user_fix_review
# Changes not staged for commit:
#   (use "git add/rm <file>..." to update what will be committed)
#   (use "git checkout -- <file>..." to discard changes in working directory)
#
#       modified:   .env.example
#       modified:   app/assets/javascripts/sync/notification.coffee
#       modified:   app/controllers/notifications_controller.rb
#       modified:   app/controllers/reviews_controller.rb
#       modified:   app/models/review.rb
#       modified:   app/views/notifications/_notifications.html.haml
#       modified:   app/views/sync/notifications/_notification.html.haml
#       deleted:    app/views/sync/users/_notification_count.html.haml
#       modified:   config/routes.rb
#
no changes added to commit (use "git add" and/or "git commit -a")
[arup@critique (permitted_user_fix_review)]$ git commit -am "Live update of notification counter after create/remove any reviews"
[permitted_user_fix_review 4b54ef4] Live update of notification counter after create/remove any reviews
 9 files changed, 33 insertions(+), 11 deletions(-)
 delete mode 100644 app/views/sync/users/_notification_count.html.haml
[arup@critique (permitted_user_fix_review)]$ git status
# On branch permitted_user_fix_review
nothing to commit, working directory clean
[arup@critique (permitted_user_fix_review)]$

git_command.sh

git reset HEAD~ .env.example; git commit --amend