Change command to update submodules

bin/manage_dotfiles.sh

@@ -74,9 +74,16 @@ install_dotfiles() {
 
 update_git_submodules() {
   git submodule update --init --recursive
-  git submodule foreach --recursive git reset --hard origin/master
-  git submodule foreach --recursive git pull origin master
-  git submodule foreach git submodule update --init --recursive
+
+  # vim/bundle/YouCompleteMe/third_party/ycmd/third_party/mrab-regex doesn't
+  # have a main/master branch, so include "hg"
+  #
+  # git fetch -a && \
+  # git checkout -b rm_detached_head && \
+  # (git checkout master || git checkout main || git checkout hg) && \
+  # git branch -D rm_detached_head && \
+  # (git reset --hard remotes/origin/master || git reset --hard remotes/origin/main || git reset --hard remotes/origin/hg)
+  git submodule foreach --recursive zsh -c 'git fetch -a && git checkout -b rm_detached_head && (git checkout master || git checkout main || git checkout hg) && git branch -D rm_detached_head && (git reset --hard remotes/origin/master || git reset --hard remotes/origin/main || git reset --hard remotes/origin/hg)'
 }
 
 compile_ycm() {