Make page title label visible

fixes MAT-740
flag=none

Test Plan:
 - Create a new page or edit an existing
 one
 - Check that there's a label that says
 "Page title" just above the page title
 text field

Change-Id: Icb550ba6c1926ba84ea085582ff47dc4b080a193
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/286212
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>
Reviewed-by: Jake Oeding <jake.oeding@instructure.com>
QA-Review: Jake Oeding <jake.oeding@instructure.com>
Product-Review: David Lyons <lyons@instructure.com>

ui/shared/wiki/jst/WikiPageEdit.handlebars

@@ -5,7 +5,7 @@
         <h1>{{title}}</h1>
         <input name="title" type="hidden" value="{{title}}">
       {{else}}
-        <label for="title" class="screenreader-only">{{#t "title_label"}}Page Title{{/t}}</label>
+        <label for="title">{{#t "title_label"}}Page Title{{/t}}</label>
         <input id="title" name="title" type="text" class="span4 title" value="{{title}}" maxlength="255" autofocus>
       {{/if}}
     {{else}}