fix js import

Author: algys

index.html

@@ -160,9 +160,9 @@ <h4>Sub-Account Generator</h4>
 			</span>
 		</div>
 	</footer>
-	<script src="//unpkg.com/@polkadot/util/bundle-polkadot-util.js"></script>
-	<script src="//unpkg.com/@polkadot/util-crypto/bundle-polkadot-util-crypto.js"></script>
-	<script src="//unpkg.com/@polkadot/keyring/bundle-polkadot-keyring.js"></script>
+	<script src="https://unpkg.com/@polkadot/util/bundle-polkadot-util.js"></script>
+	<script src="https://unpkg.com/@polkadot/util-crypto/bundle-polkadot-util-crypto.js"></script>
+	<script src="https://unpkg.com/@polkadot/keyring/bundle-polkadot-keyring.js"></script>
 
 	<script src="utilities.js"></script>
 </body>