Ahoy there, Amanda! Your Disney Cruise Line vacation will be here before you know it! 
There are no limits on non-alcoholic beverages, including your ginger beer in glass bottles. You will need to pack them in your carry-on bag, though, so that may limit how much you can carry. I suggest that you place them in a small roller bag to bring on board on embarkation day, since you will not be able to access your stateroom until the afternoon. You also need to keep your 
travel documentation in your carry-on to present at the cruise terminal. I pack my medication and phone charger in my carry-on, too. 
Just in case you change your mind, ginger beer can usually be found on board for purchase in one of the 
bars and lounges on board. The beverage team can make you a mocktail if you are looking for something a little different. Just ask!
If you have any other questions before your upcoming cruise, sail back to planDisney, Amanda.  I will raise a glass to you having a magical vacation.
Cheers!
JoVonn