docs: let hero search button take its accessible name from visible text

AccessLint flagged the label-in-name mismatch: aria-label said
"Search documentation" while the visible text says "Search the docs",
breaking voice-control activation. Drop the aria-label so the visible
label is the accessible name.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: paulOsinski

docs/layouts/home.html

@@ -25,7 +25,7 @@ <h1 class="hero-title">{{ .Title }}</h1>
           maintained by DefectDojo Inc. and the Open-Source community.
         </p>
         {{ with .Params.lead }}<p class="lead">{{ . }}</p>{{ end }}
-        <button type="button" id="ddHomeSearch" class="dd-hero-search" aria-label="Search documentation">
+        <button type="button" id="ddHomeSearch" class="dd-hero-search">
           <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" stroke-width="2" stroke="currentColor" fill="none" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><path stroke="none" d="M0 0h24v24H0z" fill="none"/><circle cx="10" cy="10" r="7"/><line x1="21" y1="21" x2="15" y2="15"/></svg>
           <span class="dd-hero-search-label">Search the docs</span>
           <span class="dd-kbd" aria-hidden="true">Ctrl K</span>