expo: bump batch to 1.21

Author: arnaud-roland

plugin/src/constants.ts

@@ -1,3 +1,3 @@
 //Define the version used in the pre-built gradle file for the batch native sdk dependency.
-export const BATCH_SDK_VERISON = "1.19.+"
-export const BATCH_DO_NOT_DISTURB_INITIAL_STATE = false;
+export const BATCH_SDK_VERISON = '1.21.+';
+export const BATCH_DO_NOT_DISTURB_INITIAL_STATE = false;