feat(): add new v5 user endpoints. add user examples.

examples/apidoc/V5/User/create-sub-uid.js

@@ -0,0 +1,21 @@
+const { RestClientV5 } = require('bybit-api');
+
+const client = new RestClientV5({
+  testnet: true,
+  key: 'apikey',
+  secret: 'apisecret',
+});
+
+client
+  .createSubMember({
+    username: 'xxxxx',
+    memberType: 1,
+    switch: 1,
+    note: 'test',
+  })
+  .then((response) => {
+    console.log(response);
+  })
+  .catch((error) => {
+    console.error(error);
+  });