[Accessibility Improvements] Add underline for all links (#55500)

Author: ashishkeshan

data/ui.yml

@@ -43,7 +43,7 @@ search:
     view_all_search_results: View more results
     no_results_found: No results found
     search_docs_with_query: Search docs for "{{query}}"
-    privacy_disclaimer: For product and service improvement purposes, the GitHub Docs team will retain questions and answers generated in the Docs search function. Please see the <a href="https://docs.github.com/privacy">GitHub Privacy Statement</a> to review how GitHub collects and uses your data.
+    privacy_disclaimer: For product and service improvement purposes, the GitHub Docs team will retain questions and answers generated in the Docs search function. Please see the <a href="https://docs.github.com/privacy"><u>GitHub Privacy Statement</u></a> to review how GitHub collects and uses your data.
   ai:
     disclaimer: <a href="https://docs.github.com/en/copilot/responsible-use-of-github-copilot-features/responsible-use-of-github-copilot-chat-in-githubcom"}>Copilot</a> uses AI. Check for mistakes.
     references: Additional docs

src/fixtures/fixtures/data/ui.yml

@@ -43,7 +43,7 @@ search:
     view_all_search_results: View more results
     no_results_found: No results found
     search_docs_with_query: Search docs for "{{query}}"
-    privacy_disclaimer: For product and service improvement purposes, the GitHub Docs team will retain questions and answers generated in the Docs search function. Please see the <a href="https://docs.github.com/privacy">GitHub Privacy Statement</a> to review how GitHub collects and uses your data.
+    privacy_disclaimer: For product and service improvement purposes, the GitHub Docs team will retain questions and answers generated in the Docs search function. Please see the <a href="https://docs.github.com/privacy"><u>GitHub Privacy Statement</u></a> to review how GitHub collects and uses your data.
   ai:
     disclaimer: <a href="https://docs.github.com/en/copilot/responsible-use-of-github-copilot-features/responsible-use-of-github-copilot-chat-in-githubcom"}>Copilot</a> uses AI. Check for mistakes.
     references: Additional docs

src/frame/components/ui/MarkdownContent/UnrenderedMarkdownContent.tsx

@@ -66,7 +66,7 @@ export const UnrenderedMarkdownContent = ({
         data-group-key={eventGroupKey}
         data-group-id={eventGroupId}
       >
-        {props.children}
+        <u>{props.children}</u>
       </a>
     )
   }

src/search/components/input/SearchOverlay.tsx

@@ -800,7 +800,7 @@ export function SearchOverlay({
               }}
               as="button"
             >
-              {t('search.overlay.give_feedback')}
+              <u>{t('search.overlay.give_feedback')}</u>
             </Link>
           </Box>
           <Text