brew: no lock is default

<Homebrew/homebrew-bundle#1509>

Author: andys8

scripts/update-brew.sh

@@ -7,5 +7,5 @@ echo "Update brew"
 brew update
 
 # Install from brewfile (created with `brew bundle dump`)
-brew bundle --file ~/dotfiles/Brewfile --no-lock
+brew bundle --file ~/dotfiles/Brewfile
 brew upgrade