Of course there is, you can CTRL+Click on parking spots on the left side of the editor window, and all changes you do to the page on the right, will be valid for all the selected gates. The window on the right will tell you how many parkings will be affected.
We'll add a special button in an upcoming update, that will automatically select only gates with jetways, so it will be even faster, so you won't have to be careful to select gates with jetways only, which is what you have to do with the current version (if you just select all gates, it will create jetways in the open too)