fix: Rephrase search label; add an aria description label to the search input

components/Search.tsx

@@ -218,7 +218,11 @@ export function Search({
       <div className="position-relative z-2">
         <form role="search" className="width-full d-flex" noValidate onSubmit={onFormSubmit}>
           <label className="text-normal width-full">
-            <span className="visually-hidden">{t`placeholder`}</span>
+            <span
+              className="visually-hidden"
+              aria-label={t`label`}
+              aria-describedby={t`description`}
+            >{t`placeholder`}</span>
             <input
               data-testid="site-search-input"
               ref={inputRef}
@@ -244,6 +248,8 @@ export function Search({
               maxLength={512}
               onChange={onSearch}
               value={localQuery}
+              aria-label={t`label`}
+              aria-describedby={t`description`}
             />
           </label>
           <button className="d-none" type="submit" title="Submit the search query." hidden />

data/ui.yml

@@ -34,13 +34,15 @@ release_notes:
   banner_text: GitHub began rolling these changes out to enterprises on
 search:
   need_help: Need help?
-  placeholder: Search topics, products...
+  placeholder: Search GitHub Docs
   loading: Loading
   no_results: No results found
   search_results_for: Search results for
   no_content: No content
   matches_displayed: Matches displayed
   search_error: An error occurred trying to perform the search.
+  description: Enter a search term to find it in the GitHub Documentation.
+  label: Search GitHub Docs
 homepage:
   explore_by_product: Explore by product
   version_picker: Version