Stop tracking Gemfile.lock in deployment tool (#306)

tools/deploy.sh

@@ -15,12 +15,6 @@ init() {
     exit -1
   fi
 
-  # Gemfile could be changed by `bundle install` in actions workflow
-  if [[ -n $(git ls-files | grep Gemfile.lock) && -n \
-  $(git status Gemfile.lock --porcelain) ]]; then
-    git checkout -- Gemfile.lock
-  fi
-
   if [[ -z $(git branch -av | grep "$PAGES_BRANCH") ]]; then
     _no_branch=true
     git checkout -b "$PAGES_BRANCH"