fix(browser): use valid urls in Request checks (#5630)

In Deno `@sentry/browser` is almost usable, but the check `new Request('')` fails silently because Deno throws a `TypeError: invalid URL` that goes to a catch block. This changes the Request call to include a valid URL `http://www.example.com` so that `@sentry/browser` can be imported in Deno without this issue.

Author: GJZwiers

packages/browser/test/integration/common/utils.js

@@ -7,7 +7,7 @@ function supportsFetch() {
 
   try {
     new Headers();
-    new Request('');
+    new Request('http://www.example.com');
     new Response();
     return true;
   } catch (e) {

packages/utils/src/supports.ts

@@ -62,7 +62,7 @@ export function supportsFetch(): boolean {
 
   try {
     new Headers();
-    new Request('');
+    new Request('http://www.example.com');
     new Response();
     return true;
   } catch (e) {