Convert some phutil_escape_html() to hsprintf()

Summary: Found by `sgrep_php -e '"...".phutil_escape_html(...)'`.

Test Plan:
/
/D1
/uiexample/
/countdown/1/
/herald/transcript/1/all/

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T2432

Differential Revision: https://secure.phabricator.com/D4869

src/applications/help/controller/PhabricatorHelpKeyboardShortcutController.php

@@ -25,14 +25,16 @@ final class PhabricatorHelpKeyboardShortcutController
     foreach ($keys as $shortcut) {
       $keystrokes = array();
       foreach ($shortcut['keys'] as $stroke) {
-        $keystrokes[] = '<kbd>'.phutil_escape_html($stroke).'</kbd>';
+        $keystrokes[] = phutil_tag('kbd', array(), $stroke);
       }
-      $keystrokes = implode(' or ', $keystrokes);
-      $rows[] =
-        '<tr>'.
-          '<th>'.$keystrokes.'</th>'.
-          '<td>'.phutil_escape_html($shortcut['description']).'</td>'.
-        '</tr>';
+      $keystrokes = array_interleave(' or ', $keystrokes);
+      $rows[] = phutil_tag(
+        'tr',
+        array(),
+        array(
+          phutil_tag('th', array(), $keystrokes),
+          phutil_tag('td', array(), $shortcut['description']),
+        ));
     }
 
     $table =