chore: remove CF-region (#13828)

Co-authored-by: Joe Au-Yeung <65426560+joeauyeung@users.noreply.github.com>

packages/trpc/server/routers/publicViewer/countryCode.handler.ts

@@ -7,8 +7,7 @@ type CountryCodeOptions = {
 export const countryCodeHandler = async ({ ctx }: CountryCodeOptions) => {
   const { req } = ctx;
 
-  const countryCode: string | string[] =
-    req?.headers?.["​cf-ipcountry"] ?? req?.headers?.["x-vercel-ip-country"] ?? "";
+  const countryCode: string | string[] = req?.headers?.["x-vercel-ip-country"] ?? "";
   return { countryCode: Array.isArray(countryCode) ? countryCode[0] : countryCode };
 };