Fix scrolling for anchors on the current page

Signed-off-by: drankou <aliaksandr.drankou@productboard.com>

.changeset/tender-pumpkins-burn.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-techdocs': patch
+---
+
+Fixed a bug where scrolling for anchors where the id starts with number didn't work for the current page.

plugins/techdocs/src/reader/components/TechDocsReaderPageContent/dom.tsx

@@ -184,7 +184,7 @@ export const useTechDocsReaderDom = (
                 navigate(`${parsedUrl.pathname}${parsedUrl.hash}`);
                 // Scroll to hash if it's on the current page
                 transformedElement
-                  ?.querySelector(`#${parsedUrl.hash.slice(1)}`)
+                  ?.querySelector(`[id="${parsedUrl.hash.slice(1)}"]`)
                   ?.scrollIntoView();
               }
             } else {