Update index.d.ts add missing randomUuid (#73)

Author: levizimmerman

index.d.ts

@@ -7,6 +7,7 @@ declare module 'react-native-aes-crypto' {
     function hmac256(ciphertext: string, key: string): Promise<string>
     function hmac512(ciphertext: string, key: string): Promise<string>
     function randomKey(length: number): Promise<string>
+    function randomUuid(): Promise<string>
     function sha1(text: string): Promise<string>
     function sha256(text: string): Promise<string>
     function sha512(text: string): Promise<string>