refactor: rename script to use kebab case, for consistency

Author: MantisClone

README.md

@@ -41,4 +41,5 @@ npm run create
 npm run pay
 npm run declare
 npm run delegate
+npm run create-many
 ```

package.json

@@ -12,7 +12,7 @@
     "declare": "node src/declarePaymentSentAndReceived.js",
     "delegate": "node src/delegateDeclarePaymentSentAndReceived.js",
     "hinkal-deposit": "node src/depositToHinkalShieldedAddress.js",
-    "createMany": "node src/createManyConcurrentRequests.js"
+    "create-many": "node src/createManyConcurrentRequests.js"
   },
   "author": "",
   "license": "ISC",