fix: add nullish coalescing operator to fix eslint error (#2087)

Author: hengrv

.changeset/young-clubs-lay.md

@@ -0,0 +1,5 @@
+---
+"create-t3-app": patch
+---
+
+Replace if statement with nullish coalescing to fix eslint error

cli/template/extras/src/trpc/react.tsx

@@ -17,9 +17,8 @@ const getQueryClient = () => {
     return createQueryClient();
   }
   // Browser: use singleton pattern to keep the same query client
-  if (!clientQueryClientSingleton) {
-    clientQueryClientSingleton = createQueryClient();
-  }
+  clientQueryClientSingleton ??= createQueryClient();
+
   return clientQueryClientSingleton;
 };