Not to worry. I've been a couple of times in Sep/Oct when it's even rainier. There's always a great deal of sunshine, with an occasional short sharp heavy shower, which can be quite entertaining on a 'wow, look at that!' basis for anyone who hasn't experienced a tropical downpour.
Average rainfall for July is 147mm. That works out to 4.7mm daily, or approximately two-tenths of an inch. This can all arrive in one single short shower, leaving the rest of the day sunny. And remember, too, that rainfall figures include during the night while everyone's asleep anyway.
I would strongly advise taking an umbrella and keeping it with you at all times. Some resorts supply them in the room, but some don't. Sod's Law says there'll be a shower just as you're heading between your room and the restaurant/bar/pool! lol
Nooooo worries.