fix(router): scroll back to the hash anchor even if it is already selected (#2265)

Co-authored-by: Divyansh Singh <40380293+brc-dd@users.noreply.github.com>

src/client/app/router.ts

@@ -187,10 +187,13 @@ export function createRouter(
               search === currentUrl.search
             ) {
               // scroll between hash anchors in the same page
-              if (hash && hash !== currentUrl.hash) {
+              if (hash) {
+                // avoid duplicate history entries when the hash is same
+                if (hash !== currentUrl.hash) {
                   history.pushState(null, '', hash)
                   // still emit the event so we can listen to it in themes
                   window.dispatchEvent(new Event('hashchange'))
+                }
                 // use smooth scroll when clicking on header anchor links
                 scrollTo(link, hash, link.classList.contains('header-anchor'))
               }