Revert "Merge pull request #5493 from LLK/revert-5478-rearrange-conference-2021"

This reverts commit 8cdd8958, reversing
changes made to 4edab692.

test/integration/footer-links.test.js

@@ -139,7 +139,7 @@ describe('www-integration footer links', () => {
         await clickText('Scratch Conference');
         let url = await driver.getCurrentUrl();
         let pathname = (new URL(url)).pathname;
-        expect(pathname).toMatch(/^\/conference\/2020\/?$/);
+        expect(pathname).toMatch(/^\/conference\/2021\/?$/);
     });
 
 });