gistfile1.txt

.....  
  if is_amazon_ec2_ami; then
    sed -i '/menuentry/ i\
  menuentry '"VyOS AMI (HVM) $NEWNAME"' { \
    linux /boot/'$NEWNAME'/vmlinuz boot=live quiet vyatta-union=/boot/'$NEWNAME' console=ttyS0 \
    initrd /boot/'$NEWNAME'/initrd.img \
  } \

    ' $BOOT_DIR/grub/grub.cfg

  else
    .....
  fi
......

gistfile2.txt

# This is the result
  menuentry VyOS AMI (HVM) 1.0.3 { 
    linux /boot/1.0.3/vmlinuz boot=live quiet vyatta-union=/boot/1.0.3 console=ttyS0 
    initrd /boot/1.0.3/initrd.img 
  } 
  
  
# I want this

menuentry VyOS AMI (HVM) 1.0.3 { 
  linux /boot/1.0.3/vmlinuz boot=live quiet vyatta-union=/boot/1.0.3 console=ttyS0 
  initrd /boot/1.0.3/initrd.img 
}