بسم الله الرحمن الرحيم
You do not fall under the category of Shariah mazur. It is not lawful for you to offer salah while urine drop fall. You should fix a schedule for going to bathroom in other time expect of jamat time so that you do not experience this problem at the time of jamat and so that you could offer salah in the state of purity.
Note: Or you should visit the bathroom at least 5 minutes before the time of jamat so that the urine drop is stopped.
Allah knows Best!
Darul Uloom Deoband