Add Firefox to the clipboard tests — radicle-explorer

Webkit still doesn’t allow to grant permissions and doesn’t allow clipboard interaction by default.

This test closes issue eb0b990

 // so that we don't run into race conditions, because there is no way to isolate
 // the clipboard in Playwright yet.
 test("copy to clipboard", async ({ page, browserName, context }) => {
   // These tests only work in Chromium, because other browsers don't support
   // changing permissions.
   if (browserName !== "chromium") {
   if (browserName === "chromium") {
     await context.grantPermissions(["clipboard-read", "clipboard-write"]);
   } else if (browserName === "webkit") {
     // We aren't able to programatically change the permissions in webkit.
     test.skip();
   }
   await context.grantPermissions(["clipboard-read", "clipboard-write"]);
   await page.goto(sourceBrowsingUrl);